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We present a research project intended to investigate the structure of Cumbre Vieja volcano in La Palma, Canary Islands, after the September-December 2021 Tajogaite eruption. Starting in the summer of 2023, we will deploy a dense network of 35 broadband seismometers provided by GFZ and University of Granada, that will add up to the ~20 permanent stations already in operation by the Spanish National Geographic Institute (IGN) and the Volcanological Institute of Canary Islands (INVOLCAN). In this way, we expect to obtain a dense coverage of the whole island with inter-station distances of about 5 km. This broadband network will be in operation for a period of about a year. Additionally, we will perform a series of large-N experiments using 200 geophones (provided by GFZ). First we will deploy these instruments along linear profiles across the island, in N-S and E-W directions. In a second stage, we will move the geophones to a bidimensional grid configuration centered at the eruption site. We estimate that inter-station distances will be of ~0.5 km in both cases, and the recording periods will span around 4-5 months per configuration. The data obtained from these deployments will be used to perform a dense receiver function analysis and ambient noise tomography to improve the knowledge of the shallow velocity structure of the volcanic rift around the eruption area down to a depth of a few km and to image the magma sources in the crust and uppermost mantle., The 28th IUGG General Assembly (IUGG2023) (Berlin 2023)

The 2021 Tajogaite eruption in La Palma, Canary Islands, was accompanied by strong volcanic tremor. In September 2021, during the first two weeks of eruption, we deployed two small-aperture seismic arrays. We chose two locations around Montaña Caldero and Llano del Jable, located about 4 km SE and 2 km NE of the eruption site. The arrays were composed of 1 three-component and 9 vertical-component short-period seismometers, sampled at 100 sps by a 12-channel data acquisition system. In each array, the receivers were spread with an aperture of about 400 m. Although they operated intermittently due to failures in the power supply related to ash fall, they provided long time series of multichannel seismic data that allow for the characterization of the syn-eruptive tremor. The analysis of the recorded wavefields reveals a persistent tremor source linked to the activity of the eruptive vents. The main component of the wavefield in the 1-3 Hz frequency band propagates with apparent slowness around 1 s/km, impinging on the arrays from directions of ~300 and 260ºN, respectively. These directions are slightly deviated from the active vents azimuths, a fact that we attribute to propagation effects produced by the topography and heterogeneous velocity structure. Subtle variations in the apparent slowness and propagation azimuths are investigated using the relative slowness estimate method, that allows for a precise determination of the apparent slowness vectors., The 28th IUGG General Assembly (IUGG2023) (Berlin 2023)

The Bransfield Strait is a seismically active extensional rift located between the Antarctic Peninsula and the South Shetland Islands. The Strait is partly located on continental crust including areas within the transition to seafloor spreading. The amphibious seismic network BRAVOSEIS is an international effort focused on the seismological research of submarine volcanoes and rift dynamics in the Bransfield Strait. This network is the onshore component of the entire network consisting of 15 broadband land stations deployed in the South Shetland Islands and Antarctic Peninsula between January 2018 and February 2020. The offshore components (network code ZX) include 9 broadband ocean bottom seismometers (OBS) across the Central Bransfield Basin and a group of 6 hydrophone moorings spanning the rift area of 200 x 100 km2, with inter-station distance of ~30 km. Additionally, a smaller offshore array consisting of 15 short-period OBSs with an aperture of 20 km and a narrow inter-station distance of ~4 km was deployed around the Orca submarine volcanic edifice south of King George Island. The data will be used to study the geodynamics of the Bransfield Strait and the evolution of the incipient rifting zone in the domain where extension has been suggested. Seismological methods will include earthquake location, source mechanism, surface wave analysis with ambient noise and earthquake data, receiver function and shear wave splitting. The results may shed light on the crustal structure and tectonic regime in the region and image the location and extent of magma accumulations related to submarine volcanic structures. Finally, the results should provide clues to assess the internal processes that occur in the submarine volcanoes of the area undergoing rifting. Waveform data are available from the GEOFON data centre, under network code 5M and are embargoed until Mar 2024. Acknowledgments: We thank all participants in the BRAVOSEIS 2018, 2019, and 2020 cruises, with a special acknowledgement to Capt. Jose Emilio Regodon and his crew at R/V Hesperides; Capt. Juan Carlos Hernandez and his crew at Sarmiento de Gamboa; Miki Ojeda, Ezequiel Gonzalez, and all the UTM staff involved in the planification and realization of the surveys. We also thank the Spanish Polar Committee and institutions involved in the management of the Spanish Antarctic campaigns and the development of the Spanish Polar Program. We are grateful for the help and support that we always find in the personnel of the Antarctic Bases, especially the Spanish Bases Juan Carlos I and Gabriel de Castilla.

Purpose: To present a practical method for calibrating the zero position of asymmetric jaws that provides higher accuracy at the central axis and improves dose homogeneity in the abutting region of half-beams. Methods: Junction doses were measured for each asymmetric jaw using the double-exposure technique and electronic portal imaging devices. The junction dose was determined as a function of jaw position. The shift in the zero jaw position (or in its corresponding potentiometer readout) required to correct for the measured junction dose could thus be obtained. The jaw calibration was then modified to introduce the calculated shift and therefore achieve an accurate zero position in order to provide a relative junction dose that was as close to zero as possible. Results: All the asymmetric jaws from four medical linear accelerators were calibrated with the new calibration procedure. Measured relative junction doses at gantry 0° were reduced from a maximum of ±40% to a maximum of ±8% for all the jaws in the four considered accelerators. These results were valid for 6 MV and 18 MV photon beams and for any combination of asymmetric jaws set to zero. The calibration was stable over a long period of time; therefore, the need for recalibrating is seldom necessary. Conclusions: Accurate calibration of the zero position of the jaws is feasible in current medical linear accelerators. The proposed procedure is fast and it improves dose homogeneity at the junction of half-beams, thus, allowing a more accurate and safer use of these techniques. © 2013 American Association of Physicists in Medicine.

The study of biomarkers and their signaling pathways has led to the development of new therapeutic strategies in a number of disorders. The purpose of the present systematic review is to provide an overview of different biomarkers in preterm newborns with corticosteroid-induced hypertrophic cardiomyopathy (CCHC). Several pathophysiological biomarkers are presented and discussed with the aim of investigating their diagnostic and prognostic value, particularly in relation to the potential progression of the disease and/or mortality in adulthood. This investigative approach may not only provide pathophysiological information on this serious drug-induced adverse effect, but also suggest novel therapeutic approaches to be applied in controlling its harmful consequences.