Underdiagnosis of osteoporotic vertebral fractures in patients with fragility fractures: retrospective analysis of over 300 patients

Osteoporosis (OP) is a silent disease unless a fracture occurs; it is a major health problem, mainly due to fragility fractures, that occur at vertebral and peripheral sites. Vertebral fractures (VF) are probably the most common fragility fractures, but they go often unrecognized. The main clinical symptoms of VF are acute and chronic back pain, spinal deformity, reduced mobility and impaired quality of life. They are frequently associated with other fragility fractures. We examined 478 patients at our outpatient clinic, who were referred for fragility fracture occurrence. The most common fragility fractures was hip fractures. However, after execution of spine X-rays in patients who had sustained hip fracture, we found that a large proportion of them had VF, which had not been reported in their medical history

EUSO science

EUSO is a mission to explore the extreme universe by the probe of Ultra High Energy Cosmic Rays (UHECRs) and UHE neutrinos. EUSO monitors a gigantic volume of atmosphere from Space and measures showers induced by UHECRs and UHE neutrinos. Scientifically, it is important to measure the energy spectrum of UHECRs well beyond GZK energy with high statistics. EUSO ensures the observation of UHECRs up to 10$^{21}$eV even in the case of GZK mechanism working, and gives us a clear picture of the existence / non-existence of the GZK effect and the behavior of the spectrum beyond GZK energy, which represents the contributions from nearby sources. The anisotropy study of UHECR arrival directions in a small scale angle above GZK energy may allow us to identify individual source, because of the limited propagation distance and the high rigidity of particles. If event clusters observed by AGASA are real, it is expected from Monte Carlo simulation that EUSO will see ~100 particles from individual brightest sources and will give us a good opportunity to test the relativity in high precision. The UHE neutrino is a unique channel to explore the universe much deeper than UHECRs. EUSO essentially can measure UHE neutrinos free from background proton showers. The number of GZK neutrino events in a EUSO three years' mission is expected to be only a few. Nevertheless, it is a definitely conceivable opportunity to begin UHE neutrino astrophysics at GZK energy

Spatial Resolution of Double-Sided Silicon Microstrip Detectors for the PAMELA Apparatus

The PAMELA apparatus has been assembled and it is ready to be launched in a satellite mission to study mainly the antiparticle component of cosmic rays. In this paper the performances obtained for the silicon microstrip detectors used in the magnetic spectrometer are presented. This subdetector reconstructs the curvature of a charged particle in the magnetic field produced by a permanent magnet and consequently determines momentum and charge sign, thanks to a very good accuracy in the position measurements (better than 3 um in the bending coordinate). A complete simulation of the silicon microstrip detectors has been developed in order to investigate in great detail the sensor's characteristics. Simulated events have been then compared with data gathered from minimum ionizing particle (MIP) beams during the last years in order to tune free parameters of the simulation. Finally some either widely used or original position finding algorithms, designed for such kind of detectors, have been applied to events with different incidence angles. As a result of the analysis, a method of impact point reconstruction can be chosen, depending on both the particle's incidence angle and the cluster multiplicity, so as to maximize the capability of the spectrometer in antiparticle tagging.Comment: 28 pages, 18 figures, submitted to Nuclear Instruments and Methods in Physics Research

Enhancement of hadron–electron discrimination in calorimeters by detection of the neutron component

In many physics experiments where calorimeters are employed, the requirement of an accurate energy measurement is accompanied by the requirement of very high hadronelectron discrimination power. Normally the latter requirement is achieved by designing a high-granularity detector with sufficient depth so that the showers can fully develop. This method has many drawbacks ranging from the high number of electronic channels to the high mass of the detector itself. Some of these drawbacks may in fact severely limit the deployment of such a detector in many experiments, most notably in space-based ones. Another method, proposed by our group and currently under investigation, relies on the use of scintillation detectors which are sensitive to the neutron component of the hadron showers. Here a review of the current status will be presented starting with the simulations performed both with GEANT4 and FLUKA. A small prototype detector has been built and has been tested in a high-energy pion/electron beam behind a "shallow" calorimeter. Results are encouraging and indicate that it is possible to enhance the discrimination power of an existing calorimeter by the addition of a small-mass neutron detector, thus paving the way for better performing astroparticle experiments. © 2010 Elsevier B.V. All rights reserved

First flight data from the PAMELA spectrometer

Abstract PAMELA is a satellite-borne experiment designed to study charged particles in the cosmic radiation, optimized in particular for antimatter components search. The experiment is mounted on the Resurs DK1 satellite that was launched on June 15th 2006 from Baikonur cosmodrome and is now collecting data from a semi-polar elliptical orbit around the Earth. The core of the PAMELA apparatus is a magnetic spectrometer, designed to determine precisely the rigidity and the absolute charge of particles crossing the detector. The tracking system is composed of six planes of silicon microstrip detectors dipped in an almost uniform magnetic field generated by a permanent magnet made of an Nd–Fe–B alloy. Some preliminary analysis about the spectrometer's performances, made using data collected since July 2006 till June 2007, are here reviewed