91 research outputs found
The effects of match-playing aspects and situational variables on achieving score-box possessions in Euro 2012 Football Championship
The aim of this study was to examine the independent and interactive effects of several match-playing aspects and situational variables on the probability of achieving score-box possessions in the 2012 European Championship. The non-clinical magnitude-based inferences method was used to interpret the true effect of the performance indicators on the response variable. The logistic regression analysis in univariate perspective showed that the probability of achieving score-box possessions was greater in the second half than in the first (OR: 1.23, P<0.05, very likely positive effect), but it was lower when a team performed a direct attack rather than a possession play (OR: 0.49, P< 0.001, most likely negative effect), when the possession started in the right path of the field than in the left (OR: 0.69, P < 0.01, most likely negative effect), and when a team played against highest ranked team (from very to most likely negative effect). In multivariate perspective, the negative effect of the direct attack to the probability of achieving score-box possessions was confirmed, and an interactive effect showed that this outcome was greater in the knockout phase of the tournament than in the relative group-stage (OR: 0.62, P< 0.05, very likely negative effect)
An Authentication Study on Grappa Spirit: The Use of Chemometrics to Detect a Food Fraud
An authenticity study on Italian grape marc spirit was carried out by gas chromatography
(GC) and chemometrics. A grape marc spirit produced in Italy takes the particular name of “grappa”,
a product which has peculiar tradition and production in its country of origin. Therefore, the
evaluation of its authenticity plays an important role for its consumption in Italy, as well as for its
exportation all around the world. For the present work, 123 samples of grappa and several kinds of
spirits were analyzed in their alcohol content by electronic densimetry, and in their volatile fraction
by gas-chromatography with a flame-ionization detector. Part of these samples (94) was employed as
a training set to compute a chemometric model (by linear discriminant analysis, LDA) and the other
part (29 samples) was used as a test set to validate it. Finally, two grappa samples seized from the
market by the Italian Customs and Monopolies Agency and considered suspicious due to their aroma
reported as non-compliant were projected onto the LDA model to evaluate the compliance with
the “grappa” class. A further one-class classification method by principal component analysis (PCA)
was carried out to evaluate the compliance with other classes. Results showed that the suspicious
samples were not recognized as belonging to any of the analyzed spirit classes, confirming the
starting hypothesis that they could be grappa samples adulterated in some way
Re-testing the JET-X Flight Module No. 2 at the PANTER facility
The Joint European X-ray Telescope (JET-X) was the core instrument of the
Russian Spectrum-X-gamma space observatory. It consisted of two identical soft
X-ray (0.3 - 10 keV) telescopes with focusing optical modules having a measured
angular resolution of nearly 15 arcsec. Soon after the payload completion, the
mission was cancelled and the two optical flight modules (FM) were brought to
the Brera Astronomical Observatory where they had been manufactured. After 16
years of storage, we have utilized the JET-X FM2 to test at the PANTER X-ray
facility a prototype of a novel X-ray polarimetric telescope, using a Gas Pixel
Detector (GPD) with polarimetric capabilities in the focal plane of the FM2.
The GPD was developed by a collaboration between INFN-Pisa and INAF-IAPS. In
the first phase of the test campaign, we have re-tested the FM2 at PANTER to
have an up-to-date characterization in terms of angular resolution and
effective area, while in the second part of the test the GPD has been placed in
the focal plane of the FM2. In this paper we report the results of the tests of
the sole FM2, using an unpolarized X-ray source, comparing the results with the
calibration done in 1996.Comment: Author's accepted manuscript posted to arXiv.org as permitted by
Springer's Self-Archiving Policy. The final publication is available at
http://rd.springer.com/article/10.1007%2Fs10686-013-9365-
Il gozzo multinodulare
SommarioSi definisce gozzo l'incremento diffuso o nodulare della ghiandola tiroidea. Il suo sviluppo è legato a fattori genetici e ambientali, di cui il più importante è rappresentato dalla carenza iodica. L'inquadramento clinico prevede un'attenta valutazione dei sintomi, dei segni, dei risultati degli esami ormonali, delle caratteristiche ecografiche e citologiche. Il trattamento deve essere poi individualizzato tenendo conto della disponibilità di molteplici opzioni terapeutiche
PolarLight: a CubeSat X-ray Polarimeter based on the Gas Pixel Detector
The gas pixel detector (GPD) is designed and developed for high-sensitivity
astronomical X-ray polarimetry, which is a new window about to open in a few
years. Due to the small mass, low power, and compact geometry of the GPD, we
propose a CubeSat mission Polarimeter Light (PolarLight) to demonstrate and
test the technology directly in space. There is no optics but a collimator to
constrain the field of view to 2.3 degrees. Filled with pure dimethyl ether
(DME) at 0.8 atm and sealed by a beryllium window of 100 micron thick, with a
sensitive area of about 1.4 mm by 1.4 mm, PolarLight allows us to observe the
brightest X-ray sources on the sky, with a count rate of, e.g., ~0.2 counts/s
from the Crab nebula. The PolarLight is 1U in size and mounted in a 6U CubeSat,
which was launched into a low Earth Sun-synchronous orbit on October 29, 2018,
and is currently under test. More launches with improved designs are planned in
2019. These tests will help increase the technology readiness for future
missions such as the enhanced X-ray Timing and Polarimetry (eXTP), better
understand the orbital background, and may help constrain the physics with
observations of the brightest objects.Comment: Accepted for publication in Experimental Astronom
Thyroid autoimmunity, thyroglobulin autoantibodies and thyroid cancer prognosis
Relevance of thyroid autoimmunity to prognosis of papillary thyroid carcinoma is still unsettled. We decided to investigate the impact of thyroid autoimmunity on prognosis of papillary thyroid carcinoma and the handling of TgAbs. We evaluated the clinical course of a large group of patients according to the presence (PTC-LT) or absence (PTC) of lymphocytic thyroiditis at histology. We studied 194 consecutive patients with a diagnosis of PTC and treated with total thyroidectomy plus ¹³¹I ablation between 2007 and 2009. Median follow-up (with 25th-75th percentiles) was 84·0 (56·4-118·0) months. The remission criteria were: basal Tg <0·2 ng/mL (or stimulated Tg <1), TgAbs <8 IU/mL (otherwise "decreasing TgAb trend", a decline of ≥20% in sequential TgAb measurements) and unremarkable imaging. PTC-LT and PTC patients had comparable treatment.TgAbs were detectable in 72·5% of PTC-LT and 16·5% of PTC patients. Time to remission was longer in the detectable than in the undetectable TgAb cohort (28·5 vs· 7·5 months [median]; HR 0·54, CI 0·35-0·83, p=0·005). When comparing PTC-LT to PTC patients the difference was maintained in the detectable TgAb (29·3 vs 13·0 months; HR 0·38, CI 0·18-0·80; p=0·01), but not in the undetectable TgAb cohort (7·7 vs 7·3 months; HR 0·90, CI 0·55-1·47; p=0·68). Using the decreasing TgAb trend, the influence of detectable TgAbs on time to remission was abolished. Thyroid autoimmunity does not influence the prognosis of papillary thyroid carcinoma. A decreasing TgAb trend seems an appropriate criterion to establish the remission of papillary thyroid carcinoma
Gas pixel detectors
Abstract With the Gas Pixel Detector (GPD), the class of micro-pattern gas detectors has reached a complete integration between the gas amplification structure and the read-out electronics. To obtain this goal, three generations of application-specific integrated circuit of increased complexity and improved functionality has been designed and fabricated in deep sub-micron CMOS technology. This implementation has allowed manufacturing a monolithic device, which realizes, at the same time, the pixelized charge-collecting electrode and the amplifying, shaping and charge measuring front-end electronics of a GPD. A big step forward in terms of size and performances has been obtained in the last version of the 0.18 μm CMOS analog chip, where over a large active area of 15×15 mm 2 a very high channel density (470 pixels/mm 2 ) has been reached. On the top metal layer of the chip, 105,600 hexagonal pixels at 50 μm pitch have been patterned. The chip has customable self-trigger capability and includes a signal pre-processing function for the automatic localization of the event coordinates. In this way, by limiting the output signal to only those pixels belonging to the region of interest, it is possible to reduce significantly the read-out time and data volume. In-depth tests performed on a GPD built up by coupling this device to a fine pitch (50 μm) gas electron multiplier are reported. Matching of the gas amplification and read-out pitch has let to obtain optimal results. A possible application of this detector for X-ray polarimetry of astronomical sources is discussed
Equalizing the Pixel Response of the Imaging Photoelectric Polarimeter On-Board the IXPE Mission
The Gas Pixel Detector is a gas detector, sensitive to the polarization of
X-rays, currently flying on-board IXPE - the first observatory dedicated to
X-ray polarimetry. It detects X-rays and their polarization by imaging the
ionization tracks generated by photoelectrons absorbed in the sensitive volume,
and then reconstructing the initial direction of the photoelectrons. The
primary ionization charge is multiplied and ultimately collected on a
finely-pixellated ASIC specifically developed for X-ray polarimetry. The signal
of individual pixels is processed independently and gain variations can be
substantial, of the order of 20%. Such variations need to be equalized to
correctly reconstruct the track shape, and therefore its polarization
direction. The method to do such equalization is presented here and is based on
the comparison between the mean charge of a pixel with respect to the other
pixels for equivalent events. The method is shown to finely equalize the
response of the detectors on board IXPE, allowing a better track reconstruction
and energy resolution, and can in principle be applied to any imaging detector
based on tracks.Comment: Accepted for publication in The Astronomical Journal. 10 pages, 19
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