1,028 research outputs found
Neoadjuvant treatment of HER2 and hormone-receptor positive breast cancer - Moving beyond pathological complete response.
Volcanic tremor at Mt. Etna, Italy, preceding and accompanying the eruption of July-August, 2001
The July 17 – August 9, 2001 flank eruption of Mt. Etna was preceded and accompanied
by remarkable changes in volcanic tremor. Based on the records of stations belonging to the permanent
seismic network deployed on the volcano, we analyze amplitude and frequency content of the seismic
signal. We find considerable changes in the volcanic tremor which mark the transition to different styles of
eruptive activity, e.g., lava fountains, phreatomagmatic activity, Strombolian explosions. In particular, the
frequency content of the signal decreases from 5 Hz to 3 Hz at our reference station ETF during episodes
of lava fountains, and further decreases at about 2 Hz throughout phases of intense lava emission. The
frequency content and the ratios of the signal amplitude allow us to distinguish three seismic sources, i.e.,
the peripheral dike which fed the eruption, the reservoir which fed the lava fountains, and the central
conduit. Based on the analysis of the amplitude decay of the signal, we highlight the migration of the dike
from a depth of ca. 5 km to about 1 km between July 10 and 12. After the onset of the effusive phase, the
distribution of the amplitude decay at our stations can be interpreted as the overall result of sources
located within the first half kilometer from the surface. Although on a qualitative basis, our findings shed
some light on the complex feeding system of Mt. Etna, and integrate other volcanological and geophysical
studies which tackle the problem of magma replenishment for the July–August, 2001 flank eruption. We
conclude that volcanic tremor is fundamental in monitoring Mt. Etna, not only as a marker of the different
sources which act within the volcano edifice, but also of the diverse styles of eruptive activity
Detection of volcano unrest from multiparameter pattern classification
Short-term forecasting of volcanic unrest requires high-rate/continuous data acquisition and monitoring of multidisciplinary data. Volcano Observatories worldwide usually adopt various tools for the automatic processing of geophysical and geochemical data streams to detect changes heralding impending eruptive activity. Here we discuss the application to multivariate data sets of a free software named KKAnalysis. The software is one of the data mining tools of the European MEDiterrranean Supersite Volcanoes (MEDSUV) project, and carries out the pattern classification of data of whatever nature provided in numerical format. We explain how this software works combining Self-Organizing Maps and fuzzy clustering. Beside numerical log files, changes of pattern characteristics are visualized as output of KKAnalysis in graphical form, by creating a sequence of colored symbols. This convenient color code highlights the development in time of the characteristics of whatever multidimensional feature vector. We also present results of applications to seismic data (volcanic tremor), in-soil radon activity, and ambient parameters (barometric pressure and air temperature measurements acquired at the same site of the radon data). We explore these applications at Mt. Etna, Italy, in time spans of various duration (from months to years), in which eruptive activity ranged from short-lived (usually from tens of minutes to hours) lava fountains to long-lasting (from months to years) lava effusions
Surveillance of enteric virus infections in a neonatal intensive care unit.
Objective. To investigate the epidemiology of neonatal viral gastroenteritis compared to
the circulation of enteric viruses in children, 109 newborns in the NICU of Mother and
Child Department and 214 children with enteritis admitted to the \u201cG. Di Cristina\u201d Children\u2019s
Hospital in Palermo were monitored for Rotavirus, Adenovirus, Astrovirus and Norovirus
infections.
Methods. Stool samples were examined by EIA to detect viral antigens. Rotavirus strains
were subjected to P- and G-typing.
Results. A Norovirus strain was detected in one neonatal stool specimen whereas an astrovirus
strain was dectected in two neonatal specimens. No Rotavirus or Adenovirus infection
was identified among the newborn infants, while Rotavirus infections were detected
in 24.8% of the symptomatic children. Type G4P[8] constituted 43.4% of the Rotavirus
strains, followed by G2P[4] (18.9%), G3P[8] (17%), G1P[8] (13.2%) and G9P[8] (1.9%).
Overall, Norovirus, Adenovirus and Astrovirus strains were responsible for 15.4% of infections
in the paediatric population with diarrhoea.
Conclusions. Viruses are diffuse agents of infection in children with enteritis. Virological
tests have to be performed to diagnose enteric infections in the paediatric population. Maternal
immunity to common Rotavirus strains combined with the limited circulation of the
emerging G9 Rotavirus type among our population may account for the absence of Rotavirus
infections in newborn infants
L'impiego di impollinatori come bioindicatori di impatto ambientale
Lo scopo dello studio è stato quello di sviluppare una approfondita conoscenza delle relazioni fra insetti impollinatori e piante con riferimento ai due aspetti seguenti:
a) il potenziale impatto di piante geneticamente modificate (PGM);
b) le possibilità di contaminazione dell’ambiente attraverso la dispersione di polline.
Tale lavoro è stato effettuato utilizzando come casi studio quello di PGM esprimenti tossine di tipo Cry per la resistenza ad insetti.
Sono state studiate tre diverse colture: colza, melanzana e pomodoro
Volcano monitoring and early warning on Mt Etna, Italy, using volcanic tremor – Methods and technical aspects
Recent activity on Mt Etna was characterized by 25 lava fountains occurred on Mt Etna in 2011 and the first
semester of 2012. In summer 2012 volcanic activity in a milder form was noticed within the Bocca Nuova
crater, before it came to an essential halt in August 2012. Together with previous unrests (e. g., in 2007-08)
these events offer rich material for testing automatic data processing and alert issue in the context of volcano
monitoring. Our presentation focuses on the seismic background radiation – volcanic tremor – which has a key
role in the surveillance of Mt Etna. From 2006 on a multi-station alert system exploiting STA/LTA ratios, has
been established in the INGV operative centre of Catania. Besides, also the frequency content has been found to
change correspondingly to the type of volcanic activity, and can thus be exploited for warning purposes. We apply
Self Organizing Maps and Fuzzy Clustering which offer an efficient way to visualize signal characteristics and its
development with time. These techniques allow to identify early stages of eruptive events and automatically flag a
critical status before this becomes evident in conventional monitoring techniques.
Changes of tremor characteristics are related to the position of the source of the signal. Given the dense seismic
network we can base the location of the sources on distribution of the amplitudes across the network. The locations
proved to be extremely useful for warning throughout both a flank eruption in 2008 as well as the 2011 lava
fountains. During all these episodes a clear migration of tremor sources towards the eruptive centres was revealed
in advance. The location of the sources completes the picture of an imminent volcanic unrest and corroborates
early warnings flagged by the changes of signal characteristics.
Automatic real time data processing poses high demands on computational efficiency, robustness of the methods
and stability of data acquisition. The amplitude based multi-station approach is not sensitive to the failure of
single stations and therefore offers a good stability. On the other hand, the single station approach, exploiting
unsupervised classification techniques, limits logistic efforts, as only one or few key stations are necessary. A
common characteristics of both strategies is their robustness to disturbances (undesired transients like earthquakes,
noise, short gaps in the continuous data flow). False alarms were not encountered so far.
A critical issue it the reliability of data storage and access. Therefore, a specific hardware cluster architecture
has been proposed for failover protection, including a Storage Area Network system. We present concepts of
the software architectures which allow easy data access following predefined user policies. We also envisage the
integration of seismic data and those originating from other scientific fields (e. g., volcano imagery, geochemistry,
deformation, gravity, magneto-telluric). This will facilitate cross-checking of evidences encountered from the
single data streams, in particular allow their immediate verification with respect to ground truth
Reply to comment by D. Carbone and D. Patanè on “Multi-disciplinary investigation on a lava fountain preceding a flank eruption: the 10 May 2008 Etna case”
Bonaccorso et al. [2011a] investigated the source and magma dynamics of the 10 May 2008 lava fountain at the South-East Crater (SEC) of Mount Etna through a multidisciplinary approach that integrated a wide data set ranging from bulk rock compositions of the erupted products to seismic tremor and long-period events, tilt and gravity signals. Using a large dataset, the study provided a robust framework in which the mechanism of the 10 May 2008 lava fountain is explained as a violent release of bubble-rich magma layer previously trapped at the top of a shallow reservoir located between −0.5 and 1.5 km above sea level (asl). This result is in agreement with recent relevant literature [Allard et al., 2005; Vergniolle and Ripepe, 2008; Aiuppa et al., 2010; Andronico and Corsaro, 2011; Bonaccorso et al., 2011b; Calvari et al., 2011; Vergniolle and Gaudemer, 2012].
In the introduction of their comment Carbone and Patanè [submitted] affirm that in their opinion the interpretation that “the lava fountain was generated by the fragmentation of a foam layer trapped at the top of shallow reservoir” is not soundly based. This comment’s conclusion is puzzling because one of the comment’s authors (D. Patanè) is also a co-author on the paper by Aiuppa et al. [2010] where the same conclusion, now criticized, was well supported (see figure 5 and conclusions of that paper). In particular, in the conclusions Aiuppa et al. [2010] reported that “The paroxysmal SEC episodes mark the violent release of a bubble-rich magma layer, with bubbles having relatively shallow reservoir ...", that is, the same conclusion now criticized in the comment. After this, the comment raises issues concerning the analysis and interpretation of gravity and tilt data in the multidisciplinary approach presented by Bonaccorso et al. [2011a]. The comment by Carbone and Patanè is divided into 4 paragraphs, labelled “1. Introduction”, “2. Gravity changes”, “3. Tilt changes” and “4. Concluding remarks” with only paragraphs 2 and 3 containing specific comments. In this reply, we address these two paragraphs, and we shall show how the assumptions underlying the comment are merely speculative and why the results presented by Bonaccorso et al.[2011a] remain valid
Comparison of Histochemical Stainings in Evaluation of Liver Fibrosis and Correlation with Transient Elastography in Chronic Hepatitis
Background and Aim. The best staining to evaluate liver fibrosis in liver hepatitis is still a debated topic. This study aimed to compare Masson's trichrome (MT), Sirius Red (SR), and orcein stainings in evaluating liver fibrosis in chronic HCV hepatitis (CHC) with semiquantitative and quantitative methods (Collagen Proportionate Area (CPA) by Digital Image Analysis (DIA)) and correlate them with transient elastography (TE). Methods. Liver stiffness evaluation of 111 consecutive patients with CHC was performed by TE. Semiquantitative staging by Metavir score system and CPA by DIA were assessed on liver biopsy stained with MT, SR, and orcein. Results. MT, SR, and orcein staining showed concordant results in 89.6% of cases in staging CHC, without significant difference in both semiquantitative and quantitative evaluations of fibrosis. TE values were concordant with orcein levels in 86.5% of the cases and with MT/RS in 77.5% (P < 0.001). No significant correlation between the grade of necroinflammatory activity and TE values was found. Conclusion. In CHC, SR/MT and orcein stainings are almost concordant and when discordant, orcein staining is better related to TE values than MT/RS. This suggests that elastic fibers play a more important role than reticular or collagenous ones in determining stiffness values in CHC
Circulating tumor DNA and disease recurrence in early stage breast cancer: From a case-control study to a prospective longitudinal trial
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Surface and deep strain at Mt. Etna volcano (Sicily, Italy) during the 2003-2004 inflation phase
We carried out a study of the seismicity and ground deformation occurred on Mount Etna volcano after the end
of 2002-2003 eruption and before the onset of 2004-2005 eruption, and recorded by the permanent local seismic
network run by Istituto Nazionale di Geofisica e Vulcanologia - Sezione di Catania and by the geodetic surveys
carried out in July 2003 and July 2004 on the GPS network. We provided a description of seismicity rate and
main seismic swarms which occurred during the investigated period. Mostly of the earthquakes are clustered in
two main clusters located on the north-eastern (E-W aligned and above the sea level) and south-eastern (NW-SE
aligned and from 3 to 8 Km below the sea level) sectors of the volcano. in order to better understand the kinematic
processes of the volcano, the 3D relocation were used to compute fault plane solutions and a selected dataset was
inverted to determine stress and strain tensors. The focal solutions on the north-eastern sector show clear left-lateral
kinematics along an E-W fault plane, in good agreement with the Pernicana fault kinematics. The focal solutions
on the south-eastern sector show a main right-lateral kinematics along a NW-SE fault plane evidencing a roughly
E-W oriented compression coupled with a N-S extension.
Surface ground deformation affecting Mt Etna and measured by GPS surveys highlights a marked inflation during
the same period, mainly visible on the western and upper sectors of the volcano; on the contrary, its eastern
side shows an exceptionally strong seawards and downwards motion with displacements ranging from 5 up to
10 cm along the coastline. The 2D geodetic strain tensor distribution was calculated on a 1.5 km spaced grid,
in order to detail the strain axes orientation above the entire GPS network. The results of the 2D geodetic strain
calculation evidenced the very strong extension (mainly along an- ENE-WSW axis) of the summit area that was
already considered as the cause of the 2004-2005 eruption; this main ENE-WSW extension continues throughout
the eastern flank, but here coupled with a WNW-ESE contraction, meaning a right-lateral shear along a NW-SE
oriented fault plane.
The opposite deformation of the eastern sector of the volcano, as measured by seismicity and ground deformation
has to be interpreted by considering the different depths of the two signals. Seismic activity along the NW-SE
alignment is, in fact, located between 3 and 8 km b.s.l. and it is then affected by the very strong additional EW
compression induced by the inflating source located by inverting GPS data just westwards and at the same
depth. Ground deformation measured by GPS at the surface, on the contrary, is mainly affected by the shallower
dynamics of the eastern flank, fastly moving towards East that produces an opposite (extension) E-W strain. It
is also meaningful, confirming the decoupling between the surface and deep strain, that all the seismicity of the
south-eastern sector lies beneath the sliding plane already modeled by geodetic data for the same time interval and
for the 2004-2006 period and also beneath the deeper one previously modeled during the 1993-1998 period when
the eastern flank velocity was much slower
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