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In the framework of S3 project "Short term earthquake forecasting" supported by Department of Civil Protection (DPC) and National Institute of Geophysics and Volcanology (INGV), a magnetotelluric (MT) station was installed in the Pollino area (southern Italy) during September 2012 by the Institute of Methodologies for Environmental Analysis (IMAA-CNR, Italy) in order to investigate possible correlation between electromagnetic signals and seismicity. For the last two years Pollino area has been characterized by swarm-type seismicity, culminating with the earthquake occurred on October 25, 2012 of magnitude MW=5.0. After the mainshock, the INGV installed a seismic station close to the MT station. In this paper, we focus the analysis on the largest event (ML=3.6) recorded during the colocated electromagnetic and seismic experiment. We applied time-frequency misfit criteria based on the continuous Morlet wavelet transform to compare the electric and seismic homologous components: this analysis confirms an overall good waveform similarity between the signals, but also some interesting differences in amplitude for frequencies above 1 Hz in correspondence of the arrival of particular seismic phases that need further investigations. [ABSTRACT FROM AUTHOR]

In this paper we present the result of a magnetotelluric (MT) investigation carried out across the High Agri Valley (HAV), southern Italy. Several MT soundings were carried out in order to obtain a ~ 15 km long 2-D resistivity model with an investigation depth of ~ 10 km. The main aim was to provide valuable data on the geological and structural setting of the HAV. The MT model was compared with preexisting geological, geophysical and seismic data. The MT model can be schematized as a superposition of three stack lateral varying layers with different thickness and resistivity values: a surficial low-medium resistivity layer associated with the Quaternary deposits and to the allochthonous units; and a deeper high resistivity layer related to the Apulia Platform, separated by a thin layer connected to the mélange zone and to the Pliocene terrigenous marine deposits. Sharp lateral resistivity variations are interpreted as faults that, on the basis of accurate focal mechanism computations, display normal-faulting kinematics. [ABSTRACT FROM AUTHOR]

Abstract: We conducted geophysical–geochemical measurements on a ∼2kmN–S profile cutting across the Pernicana Fault, one of the most active tectonic features on the NE flank of Mt. Etna. The profile passes from the unstable E flank of the volcano (to the south) to the stable N flank and significant fluctuations in electrical resistivity, self-potential, and soil gas emissions (CO2, Rn and Th) are found. The detailed multidisciplinary analysis reveals a complex interplay between the structural setting, uprising hydrothermal fluids, meteoric fluids percolating downwards, ground permeability, and surface topography. In particular, the recovered fluid circulation model highlights that the southern sector is heavily fractured and faulted, allowing the formation of convective hydrothermal cells. Although the existence of a hydrothermal system in a volcanic area does not surprise, these results have great implications in terms of flank dynamics at Mt. Etna. Indeed, the hydrothermal activity, interacting with the Pernicana Fault activity, could enhance the flank instability. Our approach should be further extended along the full extent of the boundary between the stable and unstable sectors of Etna for a better evaluation of the geohazard in this active tectonic area. [Copyright &y& Elsevier]

Abstract: Electric resistivity tomography (ERT), self-potential (SP), soil CO2 flux, and temperature are used to study the inner structure of La Fossa cone (Vulcano, Aeolian Islands). Nine profiles were performed across the cone with a measurement spacing of 20m. The crater rims of La Fossa cone are underlined by sharp horizontal resistivity contrasts. SP, CO2 flux, and temperature anomalies underline these boundaries which we interpret as structural limits associated to preferential circulation of fluids. The Pietre Cotte crater and Gran Cratere crater enclose the main hydrothermal system, identified at the centre of the edifice on the base of low electrical resistivity values (<20Ω m) and strong CO2 degassing, SP, and temperature anomalies. In the periphery, the hydrothermal activity is also visible along structural boundaries such as the Punte Nere, Forgia Vecchia, and Palizzi crater rims and at the base of the cone, on the southern side of the edifice, along a fault attributed to the NW main tectonic trend of the island. Inside the Punte Nere crater, the ERT sections show an electrical resistive body that we interpret as an intrusion or a dome. This magmatic body is reconstructed in 3D using the available ERT profiles. Its shape and position, with respect to the Pietre Cotte crater fault, allows replacing this structure in the chronology of the development of the volcano. It corresponds to a late phase of activity of the Punte Nere edifice. Considering the position of the SP, soil CO2 flux, and temperature maxima and the repartition of conductive zones related to hydrothermal circulation with respect to the main structural features, La Fossa cone could be considered as a relevant example of the strong influence of pre-existing structures on hydrothermal fluid circulation at the scale of a volcanic edifice. [Copyright &y& Elsevier]

Introduction: Buffered local anesthetics have not been studied for incision and drainage procedures in dentistry. The purpose of this prospective, randomized, double-blind study was to compare the pain of infiltration and pain of an incision and drainage procedure by using a buffered versus a nonbuffered 2% lidocaine with 1:100,000 epinephrine solution in symptomatic patients with a diagnosis of pulpal necrosis and associated acute swelling., Methods: Eighty-one adult patients were randomly divided into 2 treatment groups who received 2 infiltrations (mesial and distal to the swelling of the same formulation) by using either 2% lidocaine with 1:100,000 epinephrine buffered with 0.18 mL 8.4% sodium bicarbonate or 2% lidocaine with 1:100,000 epinephrine. Patients rated pain of needle insertion, placement, and solution deposition for each infiltration on a 170-mm visual analog scale. An incision and drainage procedure was performed, and the pain of incision, drainage, and dissection was recorded., Results: No significant differences were found between the 2 anesthetic formulations for pain of solution deposition for either the mesial or distal site infiltrations. Moderate-to-severe pain was experienced in the majority of patients with the incision and drainage procedure. No significant differences were found between the 2 formulations., Conclusions: The addition of a sodium bicarbonate buffer to 2% lidocaine with 1:100,000 epinephrine did not result in significantly decreased pain of infiltrations or significantly decreased pain of the incision and drainage procedure when compared with 2% lidocaine with 1:100,000 epinephrine in symptomatic patients with a diagnosis of pulpal necrosis and associated acute swelling., (Copyright © 2013 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.)