Starting from late May 2012, the Emilia region (Northern Italy) was severely shaken by an intense seismic sequence, originated from a ML 5.9 earthquake on May 20th, at a hypocentral depth of 6.3km, ...with thrust-type focal mechanism. In the following days, the seismic rate remained high, counting 50 ML≥2.0 earthquakes a day, on average. Seismicity spreads along a 30km east–west elongated area, in the Po river alluvial plain, in the nearby of the cities Ferrara and Modena. Nine days after the first shock, another destructive thrust-type earthquake (ML 5.8) hit the area to the west, causing further damage and fatalities. Aftershocks following this second destructive event extended along the same east-westerly trend for further 20km to the west, thus illuminating an area of about 50km in length, on the whole. After the first shock struck, on May 20th, a dense network of temporary seismic stations, in addition to the permanent ones, was deployed in the meizoseismal area, leading to a sensible improvement of the earthquake monitoring capability there. A combined dataset, including three-component seismic waveforms recorded by both permanent and temporary stations, has been analyzed in order to obtain an appropriate 1-D velocity model for earthquake location in the study area. Here we describe the main seismological characteristics of this seismic sequence and, relying on refined earthquakes location, we make inferences on the geometry of the thrust system responsible for the two strongest shocks.
•First complete analysis of the 2012 Emilia mainshocks–aftershocks seismic sequence.•New catalog of the seismic sequence including data from temporary stations•Sensible improvement in terms of the activated fault system geometry definition•The different dip of the activated fault segments is highlighted and discussed.•Basic information are provided for further specific studies and hazard scenarios.
Changes in the spatial organization, or biogeography, of colonic microbes have been observed in human inflammatory bowel disease (IBD) and mouse models of IBD. We have developed a mouse model of IBD ...that occurs spontaneously and consistently in the absence of adaptive immunity. Mice expressing tumor necrosis factor-induced protein 3 (TNFAIP3) in intestinal epithelial cells (villin-TNFAIP3) develop colitis when interbred with Recombination Activating 1-deficient mice (RAG1
−/−
). The colitis in villin-TNFAIP3 × RAG1
−/−
(TRAG) mice is prevented by antibiotics, indicating a role for microbes in this innate colitis. We therefore explored the biogeography of microbes and responses to antibiotics in TRAG colitis. Laser capture microdissection and 16S rRNA sequencing revealed altered microbial populations across the transverse axis of the colon as the inner mucus layer of TRAG, but not RAG1
−/−
, mice was infiltrated by microbes, which included increased abundance of the classes Gammaproteobacteria and Actinobacteria. Along the longitudinal axis differences in the efficacy of antibiotics to prevent colitis were evident. Neomycin was most effective for prevention of inflammation in the cecum, while ampicillin was most effective in the proximal and distal colon. RAG1
−/−
, but not TRAG, mice exhibited a structured pattern of bacterial abundance with decreased Firmicutes and Proteobacteria but increased Bacteroidetes along the proximal to distal axis of the gut. TRAG mice exhibited increased relative abundance of potential pathobionts including Bifidobacterium animalis along the longitudinal axis of the gut whereas others, like Helicobacter hepaticus were increased only in the cecum. Potential beneficial organisms including Roseburia were decreased in the proximal regions of the TRAG colon, while Bifidobacterium pseudolongulum was decreased in the TRAG distal colon. Thus, the innate immune system maintains a structured, spatially organized, gut microbiome along the transverse and longitudinal axis of the gut, and disruption of this biogeography is a feature of innate immune colitis.
In the years between 2011 and 2014, at the edge between the Apennines collapsing chain and the subducting Calabrian arc, intense seismic swarms occurred in the Pollino mountain belt. In this key ...region, <2.5 mm/yr of NE-trending extension is accommodated on an intricate network of normal faults, having almost the same direction as the mountain belt. The long-lasting seismic release consisted of different swarm episodes, where the strongest event coinciding with a
M
L
5.0 shock occurred in October 2012. This latter comes after a
M
L
four nucleated in May 2012 and followed by aseismic slip episodes. In this study, we present accurate relocations for ∼6,000 earthquakes and shear-wave splitting analysis for ∼22,600 event-station pairs. The seismicity distribution delineates two main clusters around the major shocks: in the north-western area, where the
M
L
5.0 occurred, the hypocenters are localized in a ball-shaped volume of seismicity without defining any planar distribution, whilst in the eastern area, where the
M
L
4.3 nucleates, the hypocenters define several faults of a complex system of thrusts and back-thrusts. This different behavior is also imaged by the anisotropic parameters results: a strong variability of fast directions is observed in the western sector, while stable orientations are visible in the eastern cluster. This tectonic system possibly formed as a positive flower structure but as of today, it accommodates stress on normal faults. The deep structure imaged by refined locations is overall consistent with the complex fault system recently mapped at the surface and with patterns of crustal anisotropy depicting fractures alignment at depth. The possible reactivation of inherited structures supports the important role of the Pollino fault as a composite wrench fault system along which, in the lower Pleistocene, the southward retreat of the ionian slab was accommodated; in this contest, the inversion of the faults kinematics indicates a probable southward shift of the slab edge. This interpretation may help to comprehend the physical mechanisms behind the seismic swarms of the region and defining the seismic hazard of the Pollino range: nowadays a region of high seismic hazard although no strong earthquakes are present in the historical record.
The availability of multidisciplinary and high-resolution data is a fundamental requirement to understand the physics of earthquakes and faulting. We present the Alto Tiberina Near Fault Observatory ...(TABOO), a research infrastructure devoted to studying preparatory processes, slow and fast deformation along a fault system located in the upper Tiber Valley (northern Apennines), dominated by a 60 km long low-angle normal fault (Alto Tiberina, ATF) active since the Quaternary. TABOO consists of 50 permanent seismic stations covering an area of 120 × 120 km2. The surface seismic stations are equipped with 3-components seismometers, one third of them hosting accelerometers. We instrumented three shallow (250 m) boreholes with seismometers, creating a 3-dimensional antenna for studying micro-earthquakes sources (detection threshold is ML 0.5) and detecting transient signals. 24 of these sites are equipped with continuous geodetic GPS, forming two transects across the fault system. Geochemical and electromagnetic stations have been also deployed in the study area. In 36 months TABOO recorded 19,422 events with ML ≤ 3.8 corresponding to 23.36e-04 events per day per squared kilometres; one of the highest seismicity rate value observed in Italy. Seismicity distribution images the geometry of the ATF and its antithetic/synthetic structures located in the hanging-wall. TABOO can allow us to understand the seismogenic potential of the ATF and therefore contribute to the seismic hazard assessment of the area. The collected information on the geometry and deformation style of the fault will be used to elaborate ground shaking scenarios adopting diverse slip distributions and rupture directivity models.
Se analizó un modelo explicativo del desempeño académico para conocer si los problemas de atención median la relación entre la autoeficacia académica y el desempeño académico, y si la ...ansiedad y la depresión moderan dicha relación. Participaron 326 estudiantes (11-18 años), quienes diligenciaron el Youth Self-Report (Achenback & Rescorla, 2001) y la escala de autoeficacia de Aguilar, Valencia y Martínez (2001). El desempeño académico se obtuvo del promedio de calificaciones de dos bimestres académicos en lenguaje, ciencias y matemáticas. El análisis de regresión mostró que los problemas de atención median la relación entre la autoeficacia, explicando el 40% de la varianza. La variable ansiedad-depresión moderó esta misma relación evidenciando que, a mayores niveles de ansiedad y de depresión, menor autoeficacia académica y menor desempeño académico. En suma, la relación entre la autoeficacia académica y el desempeño académico fue afectada por los problemas de conducta.
This study presents a detailed analysis of minor seismic sequences recorded in the Amatrice-Norcia area (central Italy) before 2016 when the most important seismic sequence of the last 40 years ...struck the region with the Mw 6.0 Amatrice and the Mw 6.5 Norcia earthquakes. We observe that, in the four decades before the 2016–2018 Amatrice-Visso-Norcia sequence, the instrumental seismicity rate is low, with maximum magnitudes lower than Mw 4.0, and is characterized by different types of behaviours as single shock events, swarms and minor sequences. For the first time, we relocate the minor seismicity recorded before 2016 by the Italian National Seismic Network of the Istituto Nazionale di Geofisica e Vulcanologia by applying the nonlinear inversion code NonLinLoc in a local velocity model. Revised earthquake locations of the past seismic sequences are compared to the recent 2016–2018 seismicity in order to investigate some possible correlations with the seismogenic structures reactivated in 2016. With this goal, we also integrated our new hypocentral locations with fault plane solutions and geological data to interpret our results with respect to the 2016–2018 seismicity. Our results show how some of the structures identified by the minor seismicity before 2016 were reactivated during the recent sequence, while others seismic structures remained silent. We therefore highlight how the study of minor seismic sequences provides important information about the seismogenic attitude of less active or less known seismogenic structures with consequent impact on the evaluation of the seismic hazard.
•Before 2016 seismicity in the Amatrice-Norcia area was characterized by Ml<4.0 single shock events, swarms and minor sequences•New detailed image of seismogenic structures is obtained by nonlinear inversion of the seismicity recorded before 2016•Relocated minor seismic sequences are limited at depth by a basal subhorizontal zone
We have built a complete catalog of three-dimensional (3D) hypocenter locations of earthquakes recorded in Italy from 1981 to 2018. Our catalog includes more than 420,000 events relocated by ...inverting a newly integrated dataset of ∼5.0 million P and ∼ 3.5 million S wave arrival times recorded by the Italian National Seismic Network and other permanent seismological networks operating in Italy. Available magnitudes are associated with earthquake locations from the most recent datasets and bulletins of Italian seismicity. Earthquakes are located in an updated 3D tomographic model of Italy obtained by including the Moho discontinuity and the seismic velocities of the Ionian subduction zone. We used a probabilistic, non-linear earthquake location code which provides complete information of the hypocenter solution uncertainties. Quality estimators of earthquake locations are analyzed a posteriori with an original criterion for a quantitative classification of the results, allowing users to select seismic events belonging to consistent quality classes and giving a more controlled image of the Italian instrumental seismicity for tectonic and geodynamical studies. The resulting catalog gives a new, coherent view of the spatial and temporal distribution of Italian seismicity. By selecting well constrained located events we construct the new Italian Crustal Seismogenic Layer (CSL) with a good spatial resolution, allowing us to show a comparison between seismogenic thicknesses and Moho geometry distribution. We finally present some examples of seismicity distribution in selected areas of Italy at regional and local scale relating the relocated events of our catalog with available multidisciplinary information from geology, geochemistry, geodynamical models, and historical seismicity.
•About 420 k earthquakes from 1981 to 2018 are located in the Italian 3D velocity model•The CLASS catalog reveals detailed images of the four decades long seismicity in Italy•We present the new Italian Crustal Seismogenic Layer
El presente artículo problematiza sobre la evaluación de la argumentación como proceso complejo que involucra el examen de aspectos estructurales y validez del argumento, así como la situación ...comunicativa y las características del argumentador. Tiene como objetivo analizar el uso de criterios de evaluación de la calidad de las argumentaciones en estudiantes universitarios de Brasil y Colombia. Utilizó una metodología cualitativa para el análisis de una serie de casos, cinco estudiantes universitarios de psicología brasileños y cinco colombianos, escogidos a través de muestreo intencional. La construcción de datos se realizó en contexto de aula orientado al desarrollo de competencias argumentativas (identificación, producción y evaluación) y la construcción de conocimiento curricular. El corpus de análisis correspondió a evaluaciones online realizadas por estudiantes universitarios mientras examinan las argumentaciones producidas por sus colegas durante situaciones de debate crítico. Los hallazgos muestran comunalidades y diferencias, en cuanto al empleo de criterios de calidad del argumento (dialécticos, estructurales) y de la argumentación (pragmáticos y reflexivos) en los casos analizados de los dos países. Se evidencian transformaciones intra e interindividuales en la utilización de criterios para emitir juicios sobre los argumentos y las argumentaciones producidas por otras personas.
In May-July 2012, Emilia Romagna (northern Italy) was struck by a significant seismic sequence, which was characterized by two moderate-magnitude earthquakes: a Ml 5.9 event on May 20, 2012, at ...02:03:53 UTC, and a Ml 5.8 event on May 29, 2012, at 07:00:03 UTC, about 12 km to the west of the first mainshock. The earthquake sequence produced a total of 20 casualties and severe and widespread damage, mainly to historical and commercial buildings. A detailed description of the seismic sequence can be found in Sco-gnamiglio et al. 2012, this volume. The largest of the earthquake static displacements were recorded by tens of continuous global positioning system (cGPS) stations, as described in Serpelloni et al. 2012, this volume. Most of these stations were operating with a sampling frequency of 1 Hz, and they belonged to scientific or commercial networks: RING (http://ring.gm.ingv.it); ITALPOS (http://smartnet.leica-geosystems.it); GeoTop (http://www.netgeo.it); Fondazione Geometri Emilia Romagna (http://www.gpsemiliaromagna.it; Lombardia http://www.gpslombardia.it); and Veneto (http://147.162.229.63). Some hours after the first mainshock, the sampling frequency of the near-field RING stations (SBPO and MODE) were switched to 20 Hz, thus recording the coseismic displacements produced by the May 29, 2012, earthquake at higher frequency. This sampling frequency was previously used for the detection of coseismic dynamic displacements only for the Mw 9 Tohoku-Oki 2011 event Colosimo et al. 2011b. Thus, the 20-Hz-sampling displacements for the Tohoku-Oki 2011 earthquake and the May 29, 2012, Emilia event might represent important recordings to investigate coseismic contributions at frequencies higher than 1 Hz with GPS. In the present study, after the description of the high-rate GPS (HRGPS) data analysis, we will show and compare the preliminary results. Then, for the two mainshocks, we will compare the displacements recorded by the HRGPS (1 Hz up to 20 Hz) and the strong-motion time histories (100 Hz) at MODE, where the different instruments were approximately co-located (Figure 1, inset, relative distance of ca. 90 m). …
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