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The adoption of effective strengthening techniques of historical constructions is one of the most widely debated aspects in structural engineering. Within this topic, the application of steel fiber reinforced mortar (SFRM) has been recently proposed as a low invasive and effective way to obtain a considerable structural benefit in the safety of existing masonry structure. To this purpose, in this paper the experimental results obtained on a circular masonry arches are presented. The considered specimens, subjected to a vertical increasing static load, is tested in the unstrengthened and strengthened configurations, and is part of a wider experimental campaign. After presenting and discussing the experimental results, they are compared with those relative to numerical simulations conducted by means of a discrete macro-element (DME) strategy, based on a simple mechanical scheme, able to model the nonlinear behavior of masonry structures with a limited computational effort. Such an approach is here extended to model the SFRM strengthening technique accounting for the main failure mechanisms associated to the combined presence existing masonry and the additional strengthening layer applied at the intrados of the arch. Numerical and experimental results demonstrate the efficacy of the proposed retrofitting strategy both in terms of bearing capacity and increase of ductility.

Recent seismic events occurred in areas rich of ancient remains and full of cultural and artistic heritage in terms of artworks. Earthquakes may damage buildings, but the vibrations may also induce the uplift and overturning of their content, implying irreparable loss of cultural values. The seismic assessment of objects is usually tackled modelling them as rigid blocks. This paper focuses on statues, which generally present a very complicated geometry, and proposes a general methodology involving different disciplines, for their experimental seismic assessment. The methodology is here applied to the masterpiece of “Paolo Orsi” museum in Syracuse (Italy), that is the “Venere Landolina”. Due to the complexity of statues, traditional techniques cannot be considered reliable for a proper geometry reconstruction; therefore, Terrestrial Laser Scanner (TLS) and Unmanned Aerial System (UAS) technologies are here employed to obtain a highly detailed and complete digital model. Aiming at providing a low-cost scaled physical model of the statue, a wooden specimen has been arranged employing a Computer Numerical Control (CNC) milling machine, cutting off disks from flat panels which are then superimposed and glued, progressively reconstructing the actual geometry of the statue. The specimen, able to approximately reproduce the scaled actual geometry, was then tested on a shaking table with ground motions compatible with those expected for the site where the statue is located. The obtained results are finally correlated with those expected for the real scale statue.

This paper studies the inverse problem related to the identification of the flexural stiffness of an Euler Bernoulli beam in order to reconstruct its profile starting from available response data. The proposed identification procedure makes use of energy measurements and is based on the application of a closed form solution for the static displacements of multi-stepped beams. This solution allows to easily calculate the energy related to beams modeled with arbitrary multi-step shapes subjected to a transversal roving force, and to compare it with the correspondent data obtained through direct measurements on real beams. The optimal solution which minimizes the difference between measured and calculated data is then sought by means of genetic algorithms. In the paper several different stepped beams are investigated showing that the proposed procedure allows in many cases to identify the exact beam profile. However it is shown that in some other cases different multi-step profiles may correspond to very similar static responses, and therefore to comparable minima in the optimization problem, thus complicating the profile identification problem., Comment: 27 pages, 7 figures, 6 tables

The prediction of the dynamic response of Unreinforced Masonry Structures (URMS) is a very complex task, since it is governed by material degradation and cyclic hysteric behaviour. Procedures based on nonlinear static analyses have been proposed for the seismic assessment of URMS, without properly considering hysteretic energy dissipation during the dynamic response. Even though dynamic nonlinear analyses provide satisfactory simulations of the seismic response, its application requires considerable computational effort and high user expertise for the accurate definition of the material properties, making it unsuitable for practical applications. However, simplified macro-element strategies, capable of simulating in-plane and outof-plane nonlinear responses, could represent a satisfactory engineering solution in the dynamic context. In this study the nonlinear static and dynamic in-plane behaviour of URMS was assessed by means of plane discrete models. The preliminary numerical investigation evidenced the need to define suitable hysteric constitutive laws for reliable nonlinear dynamic analyses of URMS., (undefined)

PURPOSE: This study was undertaken to investigate peroral balloon angioplasty of salivary-duct strictures (sialodochoplasty) in chronic sialadenitis, analysing the technique, results and limitations. MATERIALS AND METHODS: Nine patients underwent sialodochoplasty: seven for Stensen''s-duct strictures and two for Wharton''s-duct strictures. One patient had a double stricture of Stensen''s duct and another a salivary stone associated with a Wharton''s-duct stricture. All patients were subjected to preliminary sialography to evaluate stricture site, length and grade. Sialodochoplasty was performed after local anaesthesia and progressive dilation of the salivary-duct orifice. RESULTS: The stricture was successfully dilated in 7/9 patients. The stricture was unchanged after dilatation in one patient, and in another, it recurred after 13 months. In the patient with a double stricture of Stensen''s duct, one was resolved and the other was only partially dilated, with significant symptom improvement. One patient developed a new episode of sialadenitis after 3 months, which resolved with medical therapy. Five out of seven patients were asymptomatic at follow-up. CONCLUSIONS: Sialodochoplasty is an effective procedure in the treatment of salivary-duct strictures, improving symptoms in the majority of patients. The procedure is repeatable and can be proposed as a first-line treatment for symptomatic salivary-duct stricture.

A system for low-energy photon spectrometry using a planar germanium detector with appropriate specifications is presented. A spectrometric background investigation has been carried out with various detector shielding arrangements. The characteristics of the system for measurements of 210Pb in air-particulate matter on filters have been determined.

Introduction: Decreased airway distensibility (AD) in response to deep inspirations, as assessed by HRCT, has been associated with the severity of asthma and COPD. Aims: The current study was designed to compare the magnitude of AD by HRCT in individuals with asthma and COPD with comparable degrees of bronchial obstruction, and to explore factors that may influence it. Results: We enrolled a total of 12 asthmatics (M/F:7/5) and 8 COPD (7/1) with comparable degree of bronchial obstruction (FEV1% predicted mean±SEM: 69.1 ± 5.2% and 61.2 ± 5.0%, respectively; p = 0.31). Each subject underwent chest HRCT at FRC and at TLC. A total of 701 airways (range 20 to 38 airway per subject; 2.0 to 23.1 mm in diameter) were analyzed. AD did not differ between asthmatics and COPD (mean ± SEM: 14 ± 3.5% and 17 ± 4.3%, respectively; p = 0.58). In asthmatics, AD was significantly associated with FEV1% predicted (r2 = 0.45, p = 0.018). We found a significant correlation between the change in lung volume and the change in AD by HRCT (r2 = 0.64, p = 0.002). In COPD, we found significant correlations between AD and the RV% predicted (r2 = 0.51, p = 0.046) and the RV/TLC (r2 = 0.68, p = 0.01). Conclusions: AD was primarily affected by the dynamic ability to change lung volumes in asthmatics, and by static lung volumes in COPD. © 2013 Informa Healthcare USA, Inc.

This study sought to validate the Warrick score in the assessment of lung involvement in systemic sclerosis (SSc) and correlate the results with functional abnormalities. In addition, we propose the use of high resolution computed tomography (HRCT) indices of alveolitis and fibrosis to discriminate between different stages of the disease.Thirty-one patients with SSc (16 with the diffuse form and 15 with the limited form) underwent functional and HRCT evaluations of the lung. The semiquantitative evaluation of radiological involvement, as proposed by Warrick, provides a score for each lesion based on the severity and the extent of the pulmonary damage. In addition to the total score, indices for alveolitis and fibrosis were created. The association between each score and functional abnormalities was tested.The total Warrick score was 16+/-7.7 [mean+/-standard deviation (SD)]. The total score correlated inversely with total lung capacity (TLC) (percentage of predicted TLC) (r=-0.38; p=0.04), diffusion lung capacity for carbon monoxide (DLCO) (percentage of predicted DLCO) (r=-0.43; p=0.02) and with forced expiratory volume in 1 second (FEV1) (percentage of predicted FEV1) (r=-0.36; p=0.05). The alveolitis and fibrosis indices were 1.9+/-1.1 and 14.2+/-7.4, respectively. The alveolitis index correlated significantly with percentage of predicted DLCO (r=-0.46; p=0.01) but not with percentage of predicted TLC (r=-0.28; p=0.13). The fibrosis index correlated both with percentage of predicted DLCO (r=-0.38; p=0.04) and with percentage of predicted TLC (r=-0.35; p=0.05).Our findings confirm the diagnostic role of HRCT in assessing the extent of lung damage in SSc. Furthermore, the two indices (alveolitis and fibrosis) provide new tools for evaluating the relationship between pulmonary involvement and systemic impairment in SSc.

Today, giant hydatid cysts are fairly rare even in endemic areas. We describe a case of an extremely large hydatid cyst of the liver that was causing massive compression of the neighboring organs, giving rise to a subocclusive syndrome of the intestine. After considering the various approaches available for the treatment of this disease, it was decided that radical surgery was still the best therapeutic choice, especially when extremely large cysts are involved. In particular, in clinical situations where it is difficult to perform radical surgical procedures, less aggressive surgery followed by drug treatment should be the treatment of choice.