1,690 research outputs found

    VINEDA—Volcanic INfrasound Explosions Detector Algorithm

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    The 3D Attenuation Structure of Deception Island (Antarctica)

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    Recent Developments and Applications of Acoustic Infrasound to Monitor Volcanic Emissions

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    Volcanic ash is a well-known hazard to population, infrastructure, and commercial and civil aviation. Early assessment of the parameters that control the development and evolution of volcanic plumes is crucial to effective risk mitigation. Acoustic infrasound is a ground-based remote sensing technique—increasingly popular in the past two decades—that allows rapid estimates of eruption source parameters, including fluid flow velocities and volume flow rates of erupted material. The rate at which material is ejected from volcanic vents during eruptions, is one of the main inputs into models of atmospheric ash transport used to dispatch aviation warnings during eruptive crises. During explosive activity at volcanoes, the injection of hot gas-laden pyroclasts into the atmosphere generates acoustic waves that are recorded at local, regional and global scale. Within the framework of linear acoustic theory, infrasound sources can be modelled as multipole series, and acoustic pressure waveforms can be inverted to obtain the time history of volume flow at the vent. Here, we review near-field (<10 km from the vent) linear acoustic wave theory and its applications to the assessment of eruption source parameters. We evaluate recent advances in volcano infrasound modelling and inversion, and comment on the advantages and current limitations of these methods. We review published case studies from different volcanoes and show applications to new data that provide a benchmark for future acoustic infrasound studies.Silvio De Angelis and Alejandro Diaz-Moreno are funded by NERC grant number NE/P00105X/1. Luciano Zuccarello has received funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement No. 798480

    Uncertainty in Detection of Volcanic Activity Using Infrasound Arrays: Examples From Mt. Etna, Italy

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    SD and LZ acknowledge the support from the EUROVOLC project under the European Union’s Horizon 2020 research and innovation programme (grant agreement No. 731070). The authors thank the staff of the Istituto Nazionale di Geofisica e Vulcanologia Sezione di Catania, in particular Salvo Rapisarda, Daniele Pellegrino, Mario Pulvirenti, and Danilo Contrafatto for their valuable support in the field.The injection of gas and pyroclastic material from volcanic vents into the atmosphere is a prolific source of acoustic waves. Infrasound arrays offer efficient, cost-effective, and near real-time solutions to track the rate and intensity of surface activity at volcanoes. Here, we present a simple framework for the analysis of acoustic array data, based on least-squares beamforming, that allows to evaluate the direction and speed of propagation of acoustic waves between source and array. The algorithms include a new and computationally efficient approach for quantitative assessment of the uncertainty on array measurements based on error propagation theory. We apply the algorithms to new data collected by two 6-element infrasound arrays deployed at Mt. Etna during the period July–August 2019. Our results demonstrate that the use of two infrasound arrays allowed detecting and tracking acoustic sources from multiple craters and active vents associated with degassing and ash-rich explosions, vigorous and frequent Strombolian activity, opening of new eruptive fractures and emplacement of lava flows. Finally, we discuss the potential use of metrics based on infrasound array analyses to inform eruption monitoring operations and early warning at volcanoes characterized by episodic intensification of activity.NERC Natural Environment Research Council NE/P00105X/1European Union (EU)Geoscientists without Borders grant from the Society of Exploration Geophysic

    The epiphytic transcriptome of Podosphaera fusca and its predicted secretome

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    Comunicación presentada en formato panel en la sesión "Large-scale (omics) approaches"The cucurbit powdery mildew fungus Podosphaera fusca, is a major limiting factor for cucurbit production worldwide. Despite its agronomic and economic importance, very little is known about fundamental aspects of P. fusca biology such as obligate biotrophy and pathogenesis. In order to design novel and more durable control strategies, genomic information of P. fusca is needed. In this work we aimed to analyse the epiphytic transcriptome of P. fusca as starting point. Total RNA was isolated from mycelia and conidia, and the corresponding cDNA library was sequenced using a 454 GS FLX platform. Annotation data was acquired for 62.6% of the assembled sequences, identifying 9,713 putative genes with different orthologues. In the transcript data set, the most represented protein functions were those involved in gene expression, protein metabolism, regulation of biological process and organelle organization. Our analysis also confirmed the existence of “missing ascomycete core genes” (MACGs) found in other powdery mildew species. After analysis of the pool of fungal secreted proteins, 118 putative secreted proteins were identified, including 35 “candidate secreted effector proteins” (CSEPs) specific for P. fusca. In order to validate the in silico assembly, the expression profile of some CSEPs was analysed, which was consequent with a canonical effector expression pattern, with a maximum of expression at the beginning of the infection process 24-48 h after inoculation. Our data open the genomics era of this very important cucurbit pathogen.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech. Plan Nacional Plan I+D+I del antiguo Ministerio de Ciencia e Innovación (AGL2010-21848-CO2-01), cofinanciado con fondos FEDER (UE)

    Economic impact of the first pass effect in mechanical thrombectomy for acute ischaemic stroke treatment in Spain: a cost-effectiveness analysis from the national health system perspective

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    Health economics; Neuroradiology; StrokeEconomia de la salut; Neuroradiologia; IctusEconomía de la Salud; Neurorradiología; IctusObjective The mechanical thrombectomy (MT) benefit is related to the degree of reperfusion achieved. First pass effect (FPE) is defined as complete/near revascularisation of the large-vessel occlusion (modified Thrombolysis in Cerebral Infarction (mTICI) 2c-3) after a single device pass. This study assessed the health benefit and economic impact of achieving FPE for acute ischaemic stroke (AIS) patients from the Spanish National Health System (NHS) perspective. Design A lifetime Markov model was used to estimate incremental costs and health outcomes (measured in quality-adjusted life-years (QALYs)) of patients that achieve FPE. A subanalysis of the Systematic Evaluation of Patients Treated With Neurothrombectomy Devices for Acute Ischaemic Stroke (STRATIS) registry was performed to obtain clinical outcomes. The base case included all patients that achieved at least a final mTICI ≥2 b, while the alternative scenario included all patients regardless of their final mTICI (0–3). Treatment costs were updated to reflect current practice based on expert panel consensus, while other acute and long-term costs were obtained from a previous cost-effectiveness analysis of MT performed in Spain. Sensitivity analyses were performed to assess the model’s robustness. Setting Spanish healthcare perspective. Participants AIS patients in Spain. Interventions FPE following MT. Outcome measures The model estimated QALYs, lifetime costs and net monetary benefit for the FPE and non-FPE group, depending on the inclusion of reperfusion groups and formal care costs. Results STRATIS subanalysis estimated significantly better clinical outcomes at 90 days for the FPE group in all scenarios. In the base case, the model estimated lifetime cost saving per patient of €16 583 and an incremental QALY gain of 1.2 years of perfect health for the FPE group. Cost savings and QALY gains were greater in the alternative scenario (-€44 289; 1.75). In all scenarios, cost savings were driven by the long-term cost reduction. Conclusion Achieving FPE after MT can lead to better health outcomes per AIS patient and important cost savings for the Spanish NHS.This study was sponsored by Medtronic

    BeCAPTCHA-Type: Biometric Keystroke Data Generation for Improved Bot Detection

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    © 2023 IEEE.  Personal use of this material is permitted.  Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.This work proposes a data driven learning model for the synthesis of keystroke biometric data. The proposed method is compared with two statistical approaches based on Universal and User-dependent models. These approaches are validated on a bot detection task, using the keystroke synthetic data to improve the training process of keystroke-based bot detection systems. Our experimental framework considers a dataset with 136 million keystroke events from 168 thousand subjects. We have analyzed the performance of the three synthesis approaches through qualitative and quantitative experiments. Different bot detectors are considered based on several supervised classifiers (Support Vector Machine, Random Forest, Gaussian Naive Bayes and a Long Short-Term Memory network) and a learning framework including human and synthetic samples. The experiments demonstrate the realism of the synthetic samples. The classification results suggest that in scenarios with large labeled data, these synthetic samples can be detected with high accuracy. However, if the proposed synthetic data is nor properly modelled using massive data by bot detectors, then that data will be very difficult to detect even for the most sophisticate bot detectors. Furthermore, these results show the great potential of the presented models for improving the training of bot detection technology.This work has been supported by project BBforTAI (PID2021-127641OB-I00 MICINN/FEDER). The work of D. deAlcala is supported by a FPU Fellowship (FPU21/05785) from the Spanish MIU

    Implementación de un Manual de Gestión Energética para Edificios Atendiendo las Necesidades Presentes y Futuras del Desempeño Energético

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    This research article was developed by implementing a manual for the improvement of energy performance in buildings seeking to reduce GHG emissions and thereby mitigate climate change, taking into account the current situation of the building located in the city of Puebla, Mexico. Determining their energy consumption by accounting for electronic equipment and asking the owners how long they are used, in the same way their carbon footprint was determined to serve as a parameter for the present and future of the building, they always seek to reduce it. With the data obtained through the implementation and the corresponding energy analysis, low or no-cost improvement proposals were determined before the building enters into operation.Este artículo de investigación se desarrolló al implementar un manual para la mejora del desempeño energético en edificios buscando reducir las emisiones de GEI y con esto mitigar el cambio climático, teniendo en cuenta la situación actual del edificio ubicado en la ciudad de Puebla, México. Determinando su consumo energético por medio de contabilizar los equipos electrónicos y preguntar a los dueños el tiempo que se usan los mismos, de igual manera se determinó su huella de carbono para que nos sirva como parámetro para el presente y futuro del edificio siempre buscan reducirla. Con los datos obtenidos por medio de la implementación y el análisis energético correspondiente se determinaron propuestas de mejora de bajo o nulo costo antes de que el edificio entre en operaciones.&nbsp;&nbsp
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