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In 2010, after an ordinary snowfall, the long-span steel trusses roof covering a school building located in a small town in North Italy collapsed. The building construction was completed in 2008, while the school was opened to the public just few months before the collapse. Luckily, at the time of the collapse, the building was empty and no people died or were injured. After the collapse, the Court nominated a first Official Technical Consultant in order to investigate on the causes of failure and related responsibilities. Later on, after that the main responsibilities were identified, a second Official Technical Consultant was nominated to further investigate on few specific technical aspects related to the collapse which were not completely clarified during the first investigations. In the present work, the main attention is paid on the structural behavior of the peculiar joint elements used to connect the members and their influence on the collapse, with emphasis on the role played by geometrical imperfections and structural ductility. The lesson learned from the case study could help professional engineers in being aware on the main peculiarities and structural deficiencies of structural systems made by spatial trusses with brittle connections. [ABSTRACT FROM AUTHOR]

Despite the significant amount of research effort devoted to understanding the structural behavior of grain-silos, each year a large number of silos still fails due to bad design, poor construction, with a frequency much larger than other civil structures. In particular, silos frequently fails during large earthquakes, as occurred during the 1999 ChiChi, Taiwan earthquake when almost all the silos located in Taichung Port, 70 km far from the epicenter, collapsed. The EQE report stated that “ the seismic design of practice that is used for the design and construction of such facilities clearly requires a major revision ”. The fact indicates that actual design procedures have limits and therefore significant advancements in the knowledge of the structural behavior of silo structures are still necessary. The present work presents an analytical formulation for the assessment of the natural periods of grain silos. The predictions of the novel formulation are compared with experimental findings. [ABSTRACT FROM AUTHOR]

Crescent Shaped Braces, CSBs, are steel hysteretic devices which, thanks to their geometrical configuration, are characterized by an enhanced seismic behavior that makes them a promising alternative to conventional diagonal steel braces and other seismic devices such as Buckling Resisting Braces and Scorpions. The present work reports the results of the first experimental campaign devoted to assess the cyclic experimental behavior of CSBs. The main goals of the experimental campaign are: (i) to verify/compare the effectiveness of design formulas for the seismic design of CSB introduced by the authors in a previous research work and the predictions of a simplified non-linear model in terms of force-displacement envelop response; (ii) to assess the experimental non-linear cyclic behavior in terms of ductility capacity, energy dissipation capacity, failures. [ABSTRACT FROM AUTHOR]

In the framework of discontinuous function approximation and discontinuity interface detection, we consider an approach involving Neural Networks. In particular, we define a novel typology of Neural Network layers endowed with new learnable parameters and discontinuities in the space of the activations. These layers allow to create a new kind of Neural Networks, whose main property is to be discontinuous, able not only to approximate discontinuous functions but also to learn and detect the discontinuity interfaces. A sound theoretical analysis concerning the properties of the new discontinuous layers is performed, and some tests on discontinuous functions are proposed, in order to assess the potential of such instruments. [ABSTRACT FROM AUTHOR]

The Capparis spinosa L. has a wide distribution in the Old World from South Europe, North and East Africa, Madagascar, Southwest and Central Asia to Australia and Oceania. The consolidated traditional use of C. spinosa root as remedy against different pains in human is well known since the antiquity. Various secondary metabolites have been found in caper plant, nevertheless, few studies have been focused to the analysis of root constituents. To date, several free and glycosilated spermidine alkaloids and a more polar alkaloid, the stachydrine, have been isolated from the root of C. spinosa . Aim of this work was to improve the knowledge on the alkaloid content of the root of a Syrian sample of C. spinosa by HPLC-DAD-MS n and to propose methods to quantify these molecules in different raw extracts. A decoction, an hydroalcoholic extraction and a fractionation process to selectively recover the spermidine alkaloids were applied. To our knowledge, this is the first HPLC-DAD-MS n profile that pointed out the co-presence of stachydrine, several isobaric forms of capparispine and/or capparisine in free and glycosylated forms and some isobars of isocodonocarpine or codonocarpine as monoglycosides in extracts of C. spinosa root. The determination by HPLC/DAD for the spermidine alkaloids expressed as p -OH-coumaric acid gave values up to 3.5 mg/g dried root and the stachydrine evaluated by 1 H NMR was close to 12.5 mg/g dried root. Overall, the total alkaloids were almost doubled in hydroalcoholic extract with respect to the decoction, and the stachydrine in the cortex was almost double than in the whole root. [ABSTRACT FROM AUTHOR]

The legal establishment of protected areas is often associated with a situation of conflict arising between conservation and other human activities in particular spaces. This is primarily due to the fact that protected areas law requires changes in the behaviour of resource users. Conservation conflicts arising from the establishment of protected areas are well documented in the social science literature and attempts are made to find ways to reduce such conflicts. Yet, what of cases in which the establishment of protected areas serves to officialise existing sustainable practices and may contain an element of future proofing? Do they still generate practices of resistance and conflict? These questions are answered in this paper comparing two case studies where the authors conducted primary qualitative research: the designation of new Marine Conservation Zones under the Marine and Coastal Access Act 2009 in the Isles of Scilly (South West of England) and the designation of a new Special Area of Conservation under Council Directive 92/43/EEC (the Habitats Directive) in Barra (Scottish Outer Hebrides). Both protected areas are highly unlikely to impose changes in local sea-users’ behaviour, as in both cases they validate existing practices and are future proofing, in the sense that they offer tools that can be used to minimize the effects of potential future shocks and stresses, presently unknown. Yet, while in Scilly the new Marine Conservation Zones have been perceived as a positive addition to the seascape, in Barra the Special Area of Conservation has been heavily contested by the local community. The islanders' different perspectives towards protected areas law can be described as divergent ‘legal consciousness’. ‘Legal consciousness’ is a socio-legal concept concerned with the ways in which the law is experienced, interpreted and re-shaped by ordinary people. In our case studies, legal consciousness is a dependent variable, being the product of three main causes: history, power relationships between regulators and regulatees and risk. [ABSTRACT FROM AUTHOR]

• Beeswax-based museum objects show efflorescence. • Efflorescence contains palmitic and stearic acids. • Efflorescence arises from a solid-solid miscibility issue. • The loss of plasticizers is detrimental to mechanical properties. The Natural History Museum of Florence, and in particular "La Specola", houses several ceroplastics collections produced in Florence in the XVIII-XIX centuries by Clemente Susini and co-workers. The collections include models of fruits and plants, vertebrate and invertebrate animals, and over 1400 anatomical waxes. All models are mainly constituted by beeswax. Although extremely resistant, the models undergo a wide range of degradation processes. Periodically, a white crystalline efflorescence, commonly called "wax bloom", appears on the surface of the objects obviously impairing their aesthetical features. Many mechanisms have been hypothesized about the formation of these white exudates, but non univocal conclusions have yet been drawn. Our gas chromatography-mass spectrometry results indicate that wax bloom strongly depends on the composition of the models, being related to the presence of oils and fats originally used as plasticizers or pigments' media. Thermal and X-ray measurements indicate that a poor solid-solid miscibility between the efflorescence compounds and other beeswax components leads to phase separation followed by migration of the immiscible materials towards the model surface. Besides, X-ray diffraction reveals an increased structural order of models as compared to recent beeswax certainly correlated with the increased brittleness determined by rheology measurements. [ABSTRACT FROM AUTHOR]

Abstract: The paper presents a synergic and multidisciplinary approach where laser scanner survey, radar interferometric monitoring and finite element (FE) numerical modelling are used for expeditious and no-contact dynamic identification of monumental masonry towers. The methodology is applied to a real case of great historical interest: the “Torre del Mangia” (Mangia's tower) in Siena (Italy). The tower geometry was acquired through Terrestrial Laser Scanning (TLS) techniques. The tower oscillations were detected using an interferometric radar in “Piazza del Campo”, the square facing the Mangia's Tower, along three alignments, and movement of the structure at several heights were recorded. A FE model, built on the basis of the geometry acquired through the TLS, was used to interpret and verify the physical meaning of the experimental results. Through the discussion of the case study, the paper shows that the proposed approach can be considered as an effective and expeditious method for assessing the dynamic behavior of monumental buildings (and to plan interventions) on territorial scale. [Copyright &y& Elsevier]