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This study adopts an enhanced multiscale approach to investigate the effects of the damaging process on the structural behavior of masonry vaults with regular texture, in view of their safety assessment. The model, recently developed by the authors, links two different structural models at macro and microscale, exploiting the advantages of each formulation. At the macroscopic level a homogeneous Mindlin-Reissner shell is modeled and its constitutive response is derived by the detailed analysis of a three-dimensional (3D) masonry Unit Cell (UC) studied at microlevel. The UC is considered as the assembly of elastic bricks and damage-plastic zero-thickness interfaces, representative of both mortar and mortar-unit interaction, thus accounting for the actual geometry, arrangement and constitutive response of each constituent material. A Transformation Field Analysis procedure is used to link the two scales, speeding up the numerical simulations. Structural response of a masonry vault under differential settlements is investigated, determining its load-bearing capacity and the damaging path evolving in the structure up to collapse. The reliability of the results is proved by comparison with outcomes derived by detailed micromechanical analysis, interpreting and arguing similarities and differences.

The paper has analysed outputs generated by the development policies implemented in last decades in the South of Italy, starting from the Extraordinary Intervention (since 1950, until 1992) to the European cohesion policy (since 1996). The first one was a high-centralized development policy. Differently, the European cohesion policy is based on multilevel governance, and follows a bottom-up approach oriented to stimulate local stakeholders’ participation. The analysis, exposed in previous paragraphs, has described these two different policy experiences, the related effects on local development and on convergence between North and South of Italy and among European regions. The paper has tried to answer to a fundamental question: what factors have negatively affected the implementation of these policies, generating unexpected effects?

Buttercup (Ranunculus asiaticus, family Ranunculaceae) hybrids are considered a popular and valuable ornamental crop in Europe and are cultivated both for cut flowers and for pot or border plants. In the Liguria region of northern Italy, Ranunculus hybrid cultivation has dramatically increased over recent years and the related sanitary issues regarding virus infection need to be carefully monitored in order to maintain commercial competitiveness. Presently, ELISA is the most used diagnostic tool for virus diagnosis, but if 'mother plants' with high economic value are to be tested, more sensitive molecular diagnostic tools are needed, together with efficient protocols for in vitro culture to eradicate viruses. In this study, new RT-PCR protocols were tested on virus-infected Ranunculus hybrid plants, indexed for the 13 most important Ranunculus-infecting viruses. Rapid, uniform and effective procedures for molecular diagnosis were devised in order to promote an easy technology transfer from scientific institutions to laboratories of small and medium private enterprises. Moreover, an in vitro culture procedure was established for this species, which proved to be extremely effective in virus eradication. Advanced technology and sustainable quality production of high economic value plants are keys for future competitiveness in floriculture.

There is something still considered marginal in the literature of econ-omy: the character of the entrepreneur whose career develops in a hostile socioeconomic environment. It is made-up of abilities that fol-low no code, the fruit of evolutionary adjustments essential to under-stand peculiar kinds of small enterprise. The unforeseen legacy of a territorial competition where what counts, besides the immediate abil-ity to respond to unexpected events, is a further dose of creativity that cannot be found in geographical outposts (that welcome enterprises) hosting the modern capitalist industry. The point here is to try to as-sess how important this cognitive asset is and in which situations it clearly displays its weight in entrepreneurial activity.

Gli anziani costituiscono de facto la categoria sociale più problematica e allo stesso tempo, per forza di cose, la più grande risorsa che le istituzioni dovranno gestire dal punto di vista delle politiche pubbliche nei prossimi anni. Da un lato l’espansione delle spese per i servizi sanitari e i costi sociali da dedicare alla cura e all’assistenza, dall’altro il lavoro, in forma tradizionale, ma anche volontaristica, che i nuovi anziani sono e saranno in grado di svolgere grazie a una condizione di benessere psico-fisico migliore dei loro predecessori, costituiscono i piatti di una bilancia che dovrà essere calibrata con estrema attenzione, al fine di garantire gli equilibri sociali del prossimo futuro

Recent epidemiological studies have demonstrated that the consumption of healthy foods that are particularly rich in polyphenols might reduce the incidence of cancer and neurodegenerative diseases. In particular, chlorogenic acids (CGAs) occur ubiquitously in food and represent the most abundant polyphenols in the human diet. A number of beneficial biological effects of CGAs, such as anti-inflammatory activity, anti-carcinogenic activity, and protection against neurodegenerative diseases, have been reported. However, the molecular mechanisms at the base of these biological activities have not yet been investigated in depth. By combining NMR spectroscopy, molecular docking, surface plasmon resonance and ex vivo assays of the Ras-dependent breast cancer cell line MDA-MB-231, we contribute to the elucidation of the molecular basis of the activity of CGAs and natural extracts from green and roasted coffee beans as chemoprotective dietary supplements.

A.L., chronological age: 6.5 years old (bone age: 3.5 years old). Dysmorphic facies with hypertelorism, saddle nose, broad forehead, pointed chin. Only child, born at 41 weeks of regular pregnancy, eutocic delivery, small for gestational age (weight: 2030 g), left preauricolar appendage. At birth: direct hyperbilirubinemia, elevated serum GGT, pulmonary artery branches stenosis. Falling rate of bilirubin until normalisation after 6 months, with lab evidence of cholestasis (elevated serum GGT, bile acids and cholesterol) and hypertransaminasemia. At 4 years and 2 months old, because of a growth failure (weight and height are less than the 3rd percentile, bone age of 2 years and 9 months, non-responder to arginine-clonidine provocative test, normal female karyotype), undergo hormonal therapy for 12 months, with a catch-up growth. Clinical examination: spleen palpable 2 cm below the costal margin, mesocardiac 1/6 systolic murmur. Hypertransaminasemia (AST 100 U/L, ALT 125 U/L), lab evidence of cholestasis (serum GGT 261 U/L, cholesterol 227 mg/dl and bile acids 24.8 µmol/l), mild conjugated hyperbilirubinemia (0.45 mg/dl), elevated serum alkaline phosphatase (900 U/L) and alpha-amylase (131 U/L). Abdominal US: dilated intrahepatic bile ducts under Glisson’s capsule. Distended gallbladder. Splenomegaly (11 cm interpolar diameter). Cardiac US: patent arterial duct. Ophthalmological examination: incomplete posterior embryotoxon. Fundus oculi examination: persistent myelination, excavation of the optic disk. No vertebral anomalies. Possible diagnosis: Alagille Syndrome, confirmed by genetic testing and liver biopsy (cholestasis and paucity of the interlobular biliary ducts). The estimated incidence of Alagille syndrome is 1 in 70 000 newborns per year. A diagnosis of Alagille Syndrome may be suspected when 3 of 5 major clinical signs are present (distinctive facial features, intrahepatic cholestasis, pulmonary artery branches stenosis, posterior embryotoxon, butterfly shaped vertebrae or hemivertebra). Treatment is non-specific and includes carbohydrates, medium-chain triglycerides and vitamin supplementation. The disease usually stabilises between ages 4 and 10 years. Liver transplantation may be necessary for patients with refractory disease.

Aim of the present work is to analyse of smart laminates, obtained as staking sequence of fiber-reinforced composite laminae and composite SMA layers developing a full multiscale approach. In particular, a nonlinear MITC4 laminate finite element, based on the first-order shear deformation theory, is developed. The SMA layer constitutive relationship is determined solving at each nonlinear iteration of each time step for each integration Gauss point a nonlinear homogenization problem.

The aim of this paper is to propose a new micro-mechanical model in the context of the deductive approach used to derive interface models. This model, based on a previous study introduced previously by A. Rekik and F. Lebon [31, 32], is used to reproduce the damage in masonry by combining structural analysis and homogenization methods. The focal point of this method is to assume the existence of a third material, called interphase, which is a mixture of the two principal constituents of masonry, brick and mortar, and that is the interface between them. This new element presents a low thickness, a low stiffness and a given damage ratio. The mechanical problem of masonry, initially a 3D problem, is solved numerically as a 2D problem using finite element methods. The properties of the interface brick-mortar material are obtained using three essentials steps. First of all, an exact homogenization of a laminates is used to define a first homogeneous equivalent medium named HEM-1. After, the assumption of damaged material is taken into account by using the general framework given by M. Kachanov [13, 24, 35, 36] to evaluate the global behaviour of the damaged HEM-1 defining thus a second equivalent homogeneous medium noted HEM-2. The last step consists in using an asymptotic analysis technique which is performed to model HEM-2 as an interface or a joint. The properties of this joint are deduced from those of the HEM-2 material as proposed in former papers [2, 15, 17, 34]. Particularly, through the second homogenization are taken into account the variability of microcracks oriented family and simultaneously the opening-closure effects (unilateral behaviour). Numerically this interface is modelled with connector finite elements. Numerical results are compared to experimental ones available in the literature [7]

In the present contribution a 3D homogenization technique, able to derive the overall constitutive response of a wide range of composite materials characterized by nonlinear behavior, is proposed. The developed procedure, based on the Transformation Field Analysis (TFA), allows to study the mechanical response of the typical representative volume element (RVE) of a heterogeneous nonlinear medium assuming a nonuniform distribution for the inelastic strain field in each nonlinear phase of the analyzed composite. In particular, a piecewise linear combination of analytical functions depending on the spatial variable is chosen in order to better represent the nonuniformity of the distribution of the inelastic strain. Two different procedures to solve the evolutive problem are proposed. In order to verify the efficiency of the developed 3D nonuniform TFA procedure, a numerical application is performed in which the results obtained by the proposed technique for a periodic composite made of elastic and plastic constituents are compared with the ones carried out adopting nonlinear finite element micromechanical analyses.

Il Progetto VITROFLOR si propone di intervenire nella filiera produttiva di piante ornamentali (floricole e da vivaio) prendendo in esame la parte propagativa delle nuove accessioni, individuate a seguito di programmi di miglioramento genetico e/o di selezione, ed intervenendo, in particolare, nell’ottimizzazione delle procedure di micropropagazione e conservazione in vitro. La propagazione su larga scala è spesso un elemento condizionante lo sviluppo commerciale di una novità vegetale, influendo, a volte consistentemente, sui costi di vendita. In tale senso, la micropropagazione è particolarmente indicata per il comparto ornamentale che riesce a sostenerne i costi di produzione ed a trarne vantaggio economico. Le istituzioni di ricerca coinvolte in questo progetto sono state incaricate dalla Ditta proponente (Viavai Piante Battistini, Cesena) di studiare ed approfondire alcuni aspetti della coltura in vitro che potrebbero, una volta a regime, rendere più competitivo il sistema di moltiplicazione, a vantaggio sia della ditta di propagazione, sia degli ibridatori che ad essa si affidano per la fornitura di materiale omogeneo e sano. La tecnica, inoltre, permette di programmare la produzione di piante nell’arco dell’intera stagione vegetativa, svincolandosi dai problemi connessi con la stagionalità della propagazione tradizionale. I partners del progetto utilizzano materiale originale fornito da ibridatori e, tra le attività previste, riporteranno in questo lavoro i risultati intermedi relativi alla fase di sterilizzazione, al contenimento delle batteriosi durante la coltura, ai metodi per ottimizzare le rese di proliferazione e di radicazione e alla conservazione in crescita rallentata (a basse temperature) del materiale stock.

The aim of the present work is to develop a new finite element model for the finite strain analysis of plate structures constituted of shape memory alloy (SMA) material. A three-dimensional constitutive model for shape memory alloys able to reproduce the special thermomechanical behavior of SMA characterized by pseudoelasticity and shape memory effects is adopted. The finite strain constitutive model is thermodynamically consistent and is completely formulated in the reference configuration. A two-dimensional plate theory Q1 is proposed based on a tensor element shape function formulation. The displacement field is expressed in terms of increasing powers of the transverse coordinate. The equilibrium statement is formulated on the basis of the virtual displacement principle in a total Lagrangian format. The proposed displacement formulation is particularly suitable for the simple derivation of high-order finite elements. Numerical applications are performed to assess the efficiency and locking performance of the proposed plate finite element. Some additional numerical examples are carried out to study the accuracy and robustness of the proposed computational technique and its capability of describing the structural response of SMA devices.

A new macro-element based on the equivalent frame approach is presented to analyze the nonlinear structural response of masonry panels under monotonic lateral loadings. A nonlinear elastic response is assumed for the masonry material and the sectional response of the beam is derived performing analytical integration. A two-node equilibrated force-based (FB) beam finite element (FE) is formulated. The FE is composed of a central flexible part, characterized by a no-tension constitutive relationship, and a lumped nonlinear shear hinge arranged in series, in order to capture the main flexural and shear nonlinear mechanisms characterizing the masonry panel response. Some applications on experimental prototypes are presented, showing a very satisfactory agreement between the numerical results and the experimental outcomes.

The paper presents some numerical applications regarding the nonlinear analysis of masonry elements strengthened with fiber reinforced plastic (FRP) materials. In particular, for the modeling approach of the examined structures, a special finite element based on the Timoshenko’s theory considering a particular interpolation of the dependent variables has been proposed by the authors. The model includes special features such as interfaces and rigid offsets in order to account some peculiarities characterizing the behavior of masonry structures. The paper is organized into two main parts. In the first part the proposed model is described whilst in the second part some numerical applications are discussed.

In this paper a simplified model for evaluating the nonlinear response of unstrengthened and FRPstrengthened masonry panels is presented. The proposed model, based on simple assumptions for masonry and FRP behaviour (such as no-tension and elastic-plastic behaviour in compression of masonry material and no-compression and linear-elastic behaviour in tension of FRP material), considers the panel discretized in frame elements with different geometrical and mechanical properties. The performance of the proposed model has been validated by analyzing the response of panels tested in some recent experimental campaigns.

The present paper shows and discusses some of the results obtained within an experimental investigation carried out on ten RC beams strengthened in shear by externally bonded FRP sheets. The aim of the study is to analyze the influence that the geometrical percentage of transverse steel reinforcement could have on the FRP resisting action. In particular, the objectives of the experimental campaign have been to explore the possible interaction between FRP and steel transverse reinforcement resisting actions, analysing the deformation behaviour of the shear resisting system (FRP, transverse steel, concrete) and the modes of failure of the strengthened beams.