519 research outputs found
Adnexal Torsion in Pediatric Age: Does Bolli's Score Work? Report of Two Cases
Adnexal torsion is a surgical emergency requiring early diagnosis in order to avoid demolitive surgery. Adnexal torsion's diagnosis could be very difficult in pediatric patients because children cannot explain symptoms accurately. Furthermore reproductive organs lie high in abdomen, causing unclear examinations findings. For reducing diagnostic mistakes or delay clinical and hematological criteria could be useful. No radiological criteria (CT or MRI) should be taken in count because of the costs and the required time. By combining clinical presentation in patients with OT three useful diagnostic variables have been identified: age, duration of pain, vomiting. Presence of vomiting, short duration of abdominal pain and high CRP levels have great predictive value for the diagnosis of adnexal torsion. In those patients an exploratory laparoscopy should be performed without any doubt and/or delay. These data may aid physicians in the evaluation of abdominal pain in premenarchal girls
Detection of Volcanic Plumes by GPS: the 23 November 2013 Episode on Mt. Etna
The detection of volcanic plumes produced during explosive eruptions is important to improve our under-
standing on dispersal processes and reduce risks to aviation operations. The ability of Global Position-ing
System (GPS) to retrieve volcanic plumes is one of the new challenges of the last years in volcanic plume de -
tection. In this work, we analyze the Signal to Noise Ratio (SNR) data from 21 permanent stations of the GPS
network of the Istituto Nazionale di Geofisica e Vulcanologia, Osservatorio Etneo, that are located on the Mt.
Etna (Italy) flanks. Being one of the most explosive events since 2011, the eruption of November 23, 2013 was
chosen as a test-case. Results show some variations in the SNR data that can be correlated with the presence of
an ash-laden plume in the atmosphere. Benefits and limitations of the method are highlighted
Radiosondaggi atmosferici nell’area etnea
RADIOSONDAGGI ATMOSFERICI NELL’AREA ETNE
A lab-scale experiment to measure terminal velocity of volcanic ash
In this paper, a novel methodology to measure trajectory and terminal velocity of volcanic ash in laboratory is presented. The methodology consists of: i) planning a lab-scale experiment in order to reproduce the sedimentation processes of fine volcanic ash based on the principle of dynamic similarity; ii) realizing the experimental set-up using a glass tank filled with glycerine, a web-cam based vision system and a dedicated image post processing tool able to estimate the position and
the terminal velocity of any particle falling in the tank; iii) performing a calibration procedure to accurately estimate the uncertainty on particle velocity; iv) comparing the experimental results with estimations obtained by some particle fallout models available in literature. Our results shows that there is a good agreement between experimental terminal velocities and those obtained applying a model which includes information on particle shape. The proposed methodology allows us to investigate how the particle shape affects the sedimentation processes. Since the latter is strategic to improve the accuracy on modeling ash fallout, this work will contribute to reduce risks to aviations during explosive eruptions
Monitoring and forecasting Etna volcanic plumes
In this paper we describe the results of a project
ongoing at the Istituto Nazionale di Geofisica e Vulcanologia
(INGV). The objective is to develop and implement a
system for monitoring and forecasting volcanic plumes of
Etna. Monitoring is based at present by multispectral infrared
measurements from the Spin Enhanced Visible and
Infrared Imager on board the Meteosat Second Generation
geosynchronous satellite, visual and thermal cameras, and
three radar disdrometers able to detect ash dispersal and fallout.
Forecasting is performed by using automatic procedures
for: i) downloading weather forecast data from meteorological
mesoscale models; ii) running models of tephra dispersal,
iii) plotting hazard maps of volcanic ash dispersal and deposition
for certain scenarios and, iv) publishing the results on
a web-site dedicated to the Italian Civil Protection. Simulations
are based on eruptive scenarios obtained by analysing
field data collected after the end of recent Etna eruptions.
Forecasting is, hence, supported by plume observations carried
out by the monitoring system. The system was tested on
some explosive events occurred during 2006 and 2007 successfully.
The potentiality use of monitoring and forecasting
Etna volcanic plumes, in a way to prevent threats to aviation
from volcanic ash, is finally discussed
A Statistical Approach to Evaluate the Tephra Deposit and Ash Concentration from Puff Model Forecasts
In this paper we present a new statistical approach able to provide tephra deposit load and ash concentration
using PUFF, a lagrangian model widely used to forecast volcanic ash dispersal during volcanic crisis. We
perform a parametric study in order to analyze the influence of each input parameter on model outputs. For
this test, we simulate two eruptive scenarios like to the 2001 (Scenario 1) and 1998 (Scenario 2) Etna
eruptions using high resolution weather data and a domain of 170 x 170 km. Results show that for both
scenarios, we are able to calculate the tephra deposit load and ash concentration but the use of millions of
particles is required. Specifically, up to 33 and 220 millions of particles were necessary to accurately
predict the tephra deposit and ash concentration in air, respectively. This is approximately two orders of
magnitude larger than values typically considered running PUFF. The parametric study shows that the
horizontal diffusion coefficient, the time step of the simulations, the topography and the standard deviation
of the particle distribution greatly affect the model outputs. We also validate the model by best fit
procedures. Results show a good comparison between field data of the 2001 Etna eruption and PUFF
simulations, being inside 5 and 1/5 times the observed data, comparable with results of Eulerian models.
This work will allow to reliably outlining the areas of contaminated airspace using PUFF or any other
lagrangian model in order to define the No Fly Zone and ensure the safety to aviation operations as required
after the Eyjafjallajökull eruption
Tephra hazard assessment at Mt. Etna (Italy)
In this paper we present a probabilistic hazard assessment
for tephra fallout at Mt. Etna (Italy) associated with
both short- and long-lived eruptions. Eruptive scenarios and
eruption source parameters were defined based on the geological
record, while an advection–diffusion–sedimentation
model was used to capture the variation in wind speed and
direction with time after calibration with the field data. Two
different types of eruptions were considered in our analysis:
eruptions associated with strong short-lived plumes and eruptions
associated with weak long-lived plumes. Our probabilistic
approach was based on one eruption scenario for both
types and on an eruption range scenario for eruptions producing
weak long-lived plumes. Due to the prevailing wind direction,
the eastern flanks are the most affected by tephra deposition, with the 122 BC Plinian and 2002–2003 eruptions showing the highest impact both on infrastructures and agriculture
The peripartum period influenced the serum macromineral profile in mares
Changes in metabolic requirements during pregnancy may produce nutritional imbalances predisposing mares to pathological conditions. Therefore, we aimed to examine changes in serum macrominerals during the peripartum period in mares. Fifteen pregnant mares (Group A) were monitored starting at the 263rd day of pregnancy until the 21st day after foaling. Seven non-pregnant and non-lactating mares were used as a control group (Group B). Group A was subjected to blood sampling within 24-12 h after parturition (P) and then 7, 14 and 21 days after foaling (C1, C2, C3 weeks, respectively). Group B was subjected to regular sampling throughout the study to ensure that seasonal changes had no significant effect on studied parameters. Serum samples were analysed for serum electrolytes including sodium (NaC), potassium (KC), calcium (CaCC), phosphorus (PC), chloride (Cl) and magnesium (MgCC). Two-way repeated measures of analysis of variance (ANOVA) was applied to evaluate significant effects of peripartum on electrolyte concentrations. Group A showed a decrease in Cl concentrations (P D 0:011) after foaling and lower PC concentrations (P D 0:015) compared to Group B throughout the study. The linear regression model showed an increase in NaC concentrations (P D 0:002) and a gradual decrease in serum CaCC (P D 0:001) during pregnancy. Because the most significant changes in serum electrolytes occurred within 2 weeks before and 2 weeks after foaling, monitoring serum electrolyte concentrations would indicate whether the mare needs further mineral supplementation at this stage. The significant changes in a mare's macromineral profile that we observed over the peripartum provide enhanced knowledge about mineral interrelations and their modifications during specific physiological conditions such as late pregnancy and early postpartum
Eruption column height estimation of the 2011-2013 Etna lava fountains
In this paper, we use calibrated images collected by the video-surveillance
system of the Istituto Nazionale di Geofisica e Vulcanologia, Osservatorio
Etneo, to retrieve the height of the eruption column during the recent
Etna explosive activity. The analysis is carried out on nineteen lava fountains
from the New South East Crater dataset. The novel procedure described
in this work is achieved in three main steps: at first we calibrated
the camera, then we selected the images which recorded the maximum
phase of the eruptive activity, and finally we applied an appropriate correction
to account for the plume projection on the camera line of sight due
to the wind. The results show that the column altitudes range between 6
and 9 km (upper limit of the camera system). The comparison with the
plume height values estimated from the analysis of several SEVIRI and
MODIS satellite images, show a good agreement. Finally, for nine events
we also evaluated the thickness of the volcanic plumes in the umbrella region
which ranges between 2 and 3 km
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