758 research outputs found
The European radio network (INFREP) for studying earthquake precursors: status and preliminary results obtained on the occasion of the Dodecanese islands earthquakes (January 30, 2020; MW=5.6 and MW=5.7)
No full textThe paper describes the current status of the European radio network INFREP developed for studying earthquake precursors and reports the preliminary results obtained on the occasion of the Dodecanese islands earthquakes (MW=5.6 and MW=5.7) occurred on January 30, 2020. Information for the registration of users interested to the visualization of the trends and to download of the data acquired by the VLF/LF receivers of the INFREP network are also provided
ON THE DETECTION OF ANOMALIES IN TIME SERIES OF VLF SIGNALS RELATED TO SEISMIC ACTIVITY
No full textIn this work we present an application of the Perceptually Important Points (PIP) technique for
the analysis of time series of VLF signals collected during some earthquakes (Mw = 5.0–6.0)
occurred in the European area. The aim of the analysis is to detect “anomalies” of VLF signals
with respect to the normal variations of the data trends; these anomalies could reveal possible
radio precursors of the earthquakes. Since 2009, several radio receivers have been installed
throughout Europe in order to realize the INFREP European radio network for studying the
VLF (10–60 kHz) and LF (150–300 kHz) radio precursors of earthquakes (Biagi et al., 2011),
(Righetti et al., 2012). The analysis has been applied to earthquakes with Mw ≥ 5.0 located
inside the 5th Fresnel zone defined by each receiver and transmitter or inside a circle with a
300km radius around each receiver or transmitter. The time series which have been analyzed
are referring to earthquakes that occurred on 2009-09-06 (Mw = 5.6), 2010-02-06 (Mw = 5.0),
2010-03-08 (Mw = 6.0), and 2020-01-30 (Mw = 5.6
On the characterization of VLF radio signal propagation in atmosphere in quite solar conditions
No full textIn this work we use Very Low Frequency (VLF) radio signals, having a frequency in the bands 20-80 kHz, to study the VLF signal propagation in the atmosphere quite undisturbed conditions by selecting the signals recorded during night. As a good approximation, we can model the propagation of VLF radio signals as characterized by a ground-wave and a sky wave propagation mode. The first one generates a radio signal that propagates in the channel ground-troposphere, while the second one generates a signal which propagates using the lower ionosphere as a reflector. The VLF receivers of the INFREP (European Network of Electromagnetic Radiation) network are used. These receivers have been installed since 2009 mainly in southern and central Europe and currently the INFREP network consists of 9 receivers. A 1-minute sampling interval is used to record the amplitude of VLF signals. Long time-series of VLF signals propagating during night are extracted from recorded signals to study possible seasonal effects due to temporal variations in the physical properties of troposphere. A graph theory approach is used to investigate the spatial correlation of the aforementioned effects at different receivers. A multivariate analysis is also applied to identify common temporal changes observed at VLF receivers
Studying the temporal variations of atmosphere physical properties at different spatial and temporal scales by VLF radio signals and space geodesy techniques
No full textAbstract
In this work we study the physical variations of atmosphere at different spatial and temporal scales. The temporal evolution of the amplitude of Very Low Frequency (VLF) radio signals is used as a means to characterize the seasonal variations of atmosphere. The microwave-based GNSS and Synthetic Aperture radar (SAR) interferometry techniques are used as a means to characterize anomalies in the physical properties of atmosphere due to solar X-ray flares
Variations revealed by INFREP Radio Network in correspondence of six earthquakes with MW greater than 5.0 occurred in the Balkan Peninsula and Adriatic Sea on 26 and 27 November, 2019
No full textIn this work we analyse variations in VLF/LF radio signal amplitudes recorded by the INFREP network in the period 16 November – 6 December, 2019 characterized by very intensive seismic activities in the Balkan peninsula, Crete, and Adriatic, Aegean and Black seas. Namely, 38 earthquakes with magnitude greater than 4.0 occurred in this area during the noticed period; the most intensive of them occurred on 26 and 27 November: three events in Albania (Mw= 6.4, 5.3, 5.1), one in Crete (Mw= 6), one in Bosnia and Herzegovina (Mw= 5.4) and two in Adriatic sea (Mw= 5.4, 5.3). We study both long- and short- term variations that are already recorded in earlier studies. The long-term variations relate to changes in the amplitude intensities in periods of several days and their existence is shown in many previous studies. The recent analyses also indicate short-term variations in signal amplitude noises started about several tents of minutes before the earthquake (Nina et al. 2020). In this work, we analyse different areas using INFREP network, which allow us to study local changes in the atmosphere. In order to examine possible precursors we considered longer time started and ended 10 days before and after the most intensive of the considered earthquakes, respectively
A possible radio anomaly observed on the occasion of the MW=6.0 earthquake occurred in Dodecanese islands at the end of January 2020
No full textSince 2009, several VLF/LF radio receivers have been installed throughout Europe in order to realize a European radio network for studying the radio precursors of earthquakes, called the INFREP network. The current network has nine VLF/LF receiving stations, two in Romania and Greece, one in Italy, Austria, Portugal, Cyprus, and Serbia. The receivers can measure with 1 min sampling rate the intensity of 10 radio signals in the band VLF (10-50 kHz) and LF (150-300 kHz). The scope of existing transmitters is manifold, e.g. they are used for radio broadcast (LF), for radio- navigation or time signals and mainly for military purposes in the VLF range. At the end of January 2020 an intense seismic crisis occurred in Dodecanese Islands; the main event (Mw= 6.0) occurred on January 30. This seismic activity occurred in the "sensitive" area of the INFREP network. The analysis of the data collected by INFREP receivers has revealed clear anomalies in three VLF signals appearing some days before the main earthquake. The anomalies appear in the trends collected by the Cyprus receiver and the epicenter is inside the 5th Fresnel ellipses defined by transmitters- receiver. Here we report the data analysis and we present in detail the anomalies. The possibility that they are precursors of the quoted earthquake seems significant.
Biagi, P.F., Colella, R., Schiavulli, L., Ermini, A., Boudjada, M., Eichelberger, H., Schwingenschuh, K., Katzis, K., Contadakis, M.E., Skeberis, C., Moldovan, I.A. and Bezzeghoud, M. (2019) The INFREP Network: Present Situation and Recent Results. Open Journal of Earthquake Research,8, 101-115. https://doi.org/10.4236/ojer.2019.8200
Effect of feeding whole soybean and linseed on milk and Parmigiano Reggiano cheese lipid fraction
No full textAim of this study was to assess the effects of feeding whole soybean flakes and whole extruded
linseed to dairy cows on milk lipid fraction and Parmigiano Reggiano cheese produced from it; specifically,
PUFA and CLA contents were evaluated. For 14 weeks, a herd of 145 cows received a diet with a daily supplementation
of 1 kg of whole soybean flakes and 0.3 kg of whole extruded linseed. In the pre-trial period,
cows received an isoproteic ration devoid of both seeds. From 20 cows selected from the herd, individual milk,
bulk morning milk and vat milk samples of the entire herd were taken every 14 days. After 24 months of aging,
cheese samples were taken from twelve cheese wheels, obtained from milk produced at 0, 4, 8, 10, 12 and
14 weeks on the same days as bulk milk and vat milk samples were made. Fatty acid composition of the lipid
fraction was determined in all milk and cheese samples. Feeding whole extruded linseed and soybean flakes
has determined a decrease in short-chain fatty acids content and an increase in total CLA concentration of
the milk. Bulk milk, vat milk and aged cheese analysis samples confirmed a decrease of short-chain fatty acids
content in milk and revealed a decrease in n-6/n-3 fatty acid and in saturated/unsaturated fatty acid ratios. In
conclusion, feeding a ration including whole soybean flakes and extruded linseed can improve the nutritional
characteristics of milk and of Parmigiano Reggiano cheese, particularly with respect to their lipid fractions
Treatment of unruptured intracranial aneurysms : a surgical long-term evaluation for preoperative predictive analytics
No full textAuthor Dr.med.univ. Nico Henrique Stroh-HollyDissertation Johannes Kepler Universität Linz 202
Using VLF Time Series from the INFREP Network for the Study of Pre-Seismic Radio Anomalies
No full textThis work presents an application of the Perceptually Important Points (PIP) technique for the analysis of VLF time series. The aim of the analysis is to detect anomalies with respect to the normal variations of the data trends. Such anomalies could reveal possible radio precursors of the earthquake. Since 2009, several radio receivers have been installed throughout Europe in order to realize the INFREP European radio network for studying the VLF (10–50 kHz) and LF (150–300 kHz) radio precursors of earthquakes. The time series used for experiments was collected during the Dodecanese islands earthquakes ( MW=5.6 and MW=5.7 ) occurred on January 30, 2020
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Your guess is as good as mine: a registered report assessing physiological markers of fear and anxiety to the unknown in individuals with varying levels of intolerance of uncertainty
No full textIndividuals who score high in Intolerance of Uncertainty (IU) have a tendency to find uncertainty and the unknown aversive. However, there is a dearth of literature on the extent to which the known vs. the unknown during threatening contexts induce fear and anxiety in individuals with high IU. In the following registered report we attempted to address this question by manipulating the known and unknown in the threat of predictable and unpredictable aversive events task. Throughout the task, we measured a variety of self-report (ratings of valence and arousal) and physiological indices (skin conductance, pupil dilation, orbicularis oculi, corrugator supercilii). We collected data from 93 participants. Higher IU, relative to lower IU was associated with: (1) less discriminatory orbicularis oculi activity between cue and interstimulus interval periods across conditions, and (2) larger corrugator supercilii activity to the known predictable shock condition and smaller corrugator supercilii activity to the known unpredictable shock condition, compared to the other conditions. These findings provide evidence that IU-related biases manifest differently depending on the physiological marker of fear and anxiety and the type of known-unknown threat i.e. orbicularis oculi activity was related to generalisation across conditions, whilse corrugator supercilii activity reflected distress/relief during conditions with known threat. Ultimately, this research will inform future models of IU in relation to anxiety and stress disorders
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