INFN muon tomography demonstrator: past and recent results with an eye to near-future activities.

A short description of the muon tomography demonstrator at the INFN Laboratori Nazionali di Legnaro near Padua, Italy, is given and the principal achievements owing to the data collected at that experimental facility are presented. In particular, the feasibility studies for several applications based on the muon-tomographic technology, within national and European projects, are discussed. The experimental problems and the procedures used to improve the performance are underlined. In addition, new activities and the related detector optimization are illustrated.This article is part of the Theo Murphy meeting issue 'Cosmic-ray muography'.

Role of TachoSil® in distal pancreatectomy: a single center experience.

AIM: Distal pancreatectomies (DP) are associated with high risk of postoperative complications, and in many series higher morbidity rate than duodenopancreatectomies has been reported. To evaluate the role of a collagen sponge with human fibrinogen and thrombin film (TachoSil®) in limiting the incidence of complications after DP. METHODS: From 1996 to 2013, 221 patients have been submitted to distal pancreatectomy (± splenectomy) in our Division. A retrospective analysis has been conducted in a group of 36 consecutive and prospectively collected DP treated with intraoperative placement of TachoSil® on pancreatic stump from 2010 to 2013 (group 1). A control series of 36 consecutive patients (group 2) was matched 1:1 from hystorical database. The variables considered in the analysis were: age, gender, ASA score, pancreatic texture (hard vs. soft), histology, operative time, postoperative mortality, morbility (postoperative pancreatic fistula - POPF, postoperative hemorrage - PPH, delayed gastric emptying - DGE) and hospital stay. Differences between POPF, PPH, DGE and hospital stays between grops were investigated with χ² and t-Student test. Univariate analysis was conducted to determine factors related to POPF development. Statistical analysis was performed using freeware Microsoft Excel based program. RESULTS: Post operative mortality was 0% in both groups. POPF were registered in 36.1% (13/36) and 41.6 % (15/36) in groups 1 and 2, respectively (P=n.s.); in group 1 we didn't observe grade C POPF, while 4 patients in control group developed grade C POPF (P<0,05). No differences were found between two groups in terms of incidence of PPH and DGE. The median duration of postoperative hospital stay in group 1 was 21.8 (7-189) days compared with 31.13 (9-249) days in group 2 (P<0.001). CONCLUSION: The use of TachoSil® seems to be associated with lower incidence of grade C POPF but larger controlled trials are needed to surely assess the usefulness of TachoSil® in pancreatic surgery in order to reduce pancreatic specific complications and their severity.

Raman microspectroscopy investigation of Ag ion-exchanged glass layers.

The ion-exchange process is widely used to dope silicate glass layers with silver, aimed at controlling the Ag state in view of possible applications, ranging from light waveguide fabrication to nanostructured composite glass synthesis. The silver doped glass structure as well as its prescribed properties depend on both the preparation parameters and the subsequent treatments. Several structural aspects are still open with regard either to the modification of the glass incorporating the dopant, or to clustering phenomena silver undergoes as a function of its local concentration and state, which are in turn strongly dependent on the preparation route. Systematic characterizations of these systems are mandatory to address the role of the various synthesis parameters in giving rise to the observed features, thus pointing out the effective methodologies for the fabrication of silicate glass layers with the desired properties. In this work, the results of micro-Raman, optical absorption and photoluminescence characterizations are presented for soda-lime glass slides doped with silver by Ag(+)-Na+ exchange and subsequent thermal treatments in air. In particular, a cross-section profiling analysis by Raman micro-spectroscopy was performed on Ag ion-exchanged samples after treatment at some different temperatures. The experimental findings allow to elucidate the role of the treatment temperature in the clustering process related to the local Ag concentration inside the exchanged glass layer.

Clinical features, diagnostic and therapeutic approaches to haematogenous vertebral osteomyelitis.

This article review the clinical features and the diagnostic approach to haematogenous vertebral osteomyelitis in order to optimise treatment strategies and follow-up assessment. Haematogenous spread is considered to be the most important route: the lumbar spine is the most common site of involvement for pyogenic infection and the thoracic spine for tuberculosis infection. The risk factors for developing haematogenous vertebral osteomyelitis are different among old people, adults and children: the literature reports that the incidence seems to be increasing in older patients. The source of infection in the elderly has been related to the use of intravenous access devices and the asymptomatic urinary infections. In young patients the increase has been correlated with the growing number of intravenous drug abusers, with endocarditis and with immigrants from areas where tuberculosis is still endemic. The onset of symptoms is typically insidious with neck or back pain often underestimated by the patient. Fever is present in 10-45% of patients. Spinal infections may cause severe neurological compromise in few cases, but mild neurological deficit, limited to one or two nerve roots, was detected in 28-35% of patients. The diagnosis of haematogenous vertebral osteomyelitis may be very difficult, as the symptoms can be sometimes not specific, vague or almost absent. The usual delay in diagnosis has been reported to be two to four months, despite the use of imaging techniques: in the early diagnosis of vertebral ostemyelitis is important the role of bone scintigraphy. The general principles for the management of spine infections are non operative, consisting of external immobilization and intravenous antibiotics, followed by oral antibiotics. Indications for surgery should be given in case of absence of clinical improvement after 2-3 weeks of intravenous antibiotics, persistent back pain and systemic effects of chronic infection and with presence or progression of neurological deficit in elderly or in cervical infection. Chronic ostemyelitis may require surgery in case of a development of biomechanical instability and/or a vertebral collapse with progressive deformity.

Retrograde intramedullary osteosynthesis of femoral fracture: preliminary results of Maggiore Hospital.

The Distal Femoral Nail (DFN), Mathys Medical Ltd. Switzerland) was used in our division for the treatment of fractures of the distal metaepiphysis, and in some cases of the diaphysis, of the femur. A total of 16 cases treated over 30 months, between October 2000 and March 2003 (minimum 6, maximum 61 months), were analyzed retrospectively. A total of 11 metaepiphyseal fractures (65%) and 6 diaphyseal fractures (35%) were treated. Consolidation of the fracture was observed in 15 cases out of 16 (equal to 93.8%) with a mean time of 140 days (minimum 120 days, maximum 240 days) after surgery. Mean flexion of the knee equal to 90 degrees and 3 cases of stiffness with lower mobility at 45 degrees were observed: in 2 cases stiffness was of extra-articular origin caused by exuberant bone callus. There were no iatrogenic complications of the vascular type, nor were there infections, or cases of implant loosening. Shortening (1 cm) in a type B2 fracture (based on the AO classification) was observed. The results we obtained suggest that DFN represents a valid alternative to the open treatment of fractures of the distal metaphysis of the femur; in cases of patients with multiple trauma or in elderly patients where invasiveness is reduced, importance is awarded to less blood loss, a shorter amount of time required for surgery, and early mobilization and weight-bearing.

Multivariate analysis as a tool for Ion Beam Induced Luminescence (IBIL) spectra interpretation.

Multivariate analysis is used to identify the number and wavelength position of components evolving during irradiation with different rates in Ion Beam Induced Luminescence (IBIL) spectra. The method, based on the study of the eigenvectors of the matrix whose elements are the luminescence intensity values for different wavelengths and fluences, is tested on two different simulated cases and on experimental IBIL spectra collected from a polysiloxane scintillators.

Stress-induced optical effects in Ag(+)-Na(+) ion-exchanged glass waveguides.

Birefringence data on Ag(+)-Na(+) ion-exchanged planar waveguides are presented that are experimentally determined by a high-frequency polarimetric technique. The examined systems exhibit positive stress-induced birefringence across the whole exchanged regions, corresponding to compressive stress fields of the order of 10(2) MPa. Furthermore, refractive-index profiles have been compared with compositional secondary-ion-mass spectrometry in-depth profiles and show that, in the case of silver-sodium exchange, the stress contribution to the index change is negligible with respect to the compositional one.