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In a previous baboon-study, a total of 29 genes were identified for clinical outcome prediction of the hematologic, acute, radiation, syndrome (H-ARS) severity. Among them, four genes (FDXR, DDB2, POU2AF1, WNT3) appeared promising and were validated in five leukemia patients. Within this study, we sought further in-vivo validation in a larger number of whole-body irradiated patients. Peripheral blood was drawn from 10 leukemia patients before and up to 3 days during a fractionated (2 Gy/day) total-body irradiation (TBI) with 2–12Gy. After RNA-isolation, gene expression (GE) was evaluated on 31 genes widely used in biodosimetry and H-ARS prediction employing qRT-PCR. A customized low-density-array (LDA) allowed simultanously analyzing all genes, the 96-well format further examined the four most promising genes. Fold-changes (FC) in GE relative to pre-irradiation were calculated. Five patients suffering from acute-lymphoblastic-leukemia (ALL) respectively non-Hodgkin-lymphoma (NHL) revealed sufficient RNA-amounts and corresponding lymphocyte and neutrophile counts for running qRT-PCR, while acute-myeloid-leukemia (AML) and one myelofibrosis patient could not supply enough RNA. Generally, 1–2µg total RNA was isolated, whereas up to 10-fold differences in RNA-quantities (associated suppressed GE-changes) were identified among pre-exposure and exposure samples. From 31 genes, 23 were expressed in at least one of the pre-exposure samples. Relative to pre-exposure, the number of expressed genes could halve at 48 and 72h after irradiation. Using the LDA, 13 genes were validated in human samples. The four most promising genes (vid. sup.) were either undetermined or too close to pre-exposure. However, they were measured using the more sensitive 96-well format, except WNT3, which wasn´t detectable. As in previous studies, an opposite regulation in GE for FDXR in leukemia patients (up-regulated) relative to baboons (down-regulated) was reconfirmed. Radiation-induced GE-changes of DDB2 (up-regulated) and POU2AF1 (down-regulated) behaved similarly in both species. Hence, 16 out of 23 genes of two species showed GE-changes in the same direction, and up-regulated FDXR as in human studies were revalidated. Identified genes for H-ARS severity prediction, previously detected in baboons, were validated in ALL but not in AML patients. Limitations related to leukemia type, associated reduced RNA amounts, suppressed GE changes, and methodological challenges must be considered as factors negatively affecting the total number of validated genes. Based on that, we propose additional controls including blood cell counts and preferably fluorescence-based RNA quantity measurements for selecting promising samples and using a more sensitive 96-well format for candidate genes with low baseline copy numbers. [ABSTRACT FROM AUTHOR]

With a view to achieving sustainable development and a circular economy, this work focused on the possibility to valorize a secondary waste stream of recycled carbon fiber (rCF) to produce a 3D printing usable material with a PA6,6 polymer matrix. The reinforcing fibers implemented in the research are the result of a double-recovery action: starting with pyrolysis, long fibers are obtained, which are used to produce non-woven fabrics, and subsequently, fiber agglomerate wastes obtained from this last process are ground in a ball mill. The effect of different amounts of reinforcement at 5% and 10% by weight on the mechanical properties of 3D-printed thermoplastic composites was investigated. Although the recycled fraction was successfully integrated in the production of filaments for 3D printing and therefore in the production of specimens via the fused deposition modeling technique, the results showed that fibers did not improve the mechanical properties as expected, due to an unsuitable average size distribution and the presence of a predominant dusty fraction ascribed to the non-optimized ball milling process. PA6,6 + 10 wt.% rCF composites exhibited a tensile strength of 59.53 MPa and a tensile modulus of 2.24 GPa, which correspond to an improvement in mechanical behavior of 5% and 21% compared to the neat PA6,6 specimens, respectively. The printed composite specimens loaded with the lowest content of rCF provided the greatest improvement in strength (+9% over the neat sample). Next, a prediction of the "optimum" critical length of carbon fibers was proposed that could be used for future optimization of recycled fiber processing. [ABSTRACT FROM AUTHOR]

Up to now, fiber-reinforced composites with thermoplastic matrix have seen limited fields of use in the structural scope due to their high viscosity in the molten state, which results in poor impregnability of the reinforcement, leading to mechanical properties of the finished product that are not comparable to those of thermosets. Although the latter still dominate the various sectors of automotive, aerospace, transportation and construction, new applications involving the production of thermoplastic composites are growing rapidly, offering new approaches to the solution of this problem. The aim of this work is to study and evaluate the state of the art on the manufacturing processes of thermoplastic matrix composite, analyzing the parameters that come into play and that most influence the process and material performance. The advantages of film stacking and powder impregnation techniques are contrasted by the versatility of hybrid fabrics and, at the same time, parameters such as pressure and temperature must be carefully considered. A description of different thermoplastic composite processes such as powder impregnation, film stacking molding, hybrid woven fabric, hybrid yarn and products follows, which represent the current possibilities to move from a thermosetting matrix composite to a thermoplastic one, upon which the concept of sustainability is based. This article wants to present an overview of research that has been done in manufacturing thermoplastic reinforced composites and will serve as a baseline and aid for further research and development efforts. [ABSTRACT FROM AUTHOR]

Masonry structures constitute the great majority of buildings in historical centers where construction activities were carried out by adding structural portions to pre-existing ones: as a result, masonry aggregates are currently the most common structural typology in such contexts. The structural behavior of masonry aggregates, which are complex systems of different buildings interacting with each other, is generally affected by several factors, such as the different steps of construction, uncertainties about interlocking between walls, presence of different and irregular masonry textures and multi-leaf walls, which make such a structural typology very difficult to study. During recent seismic events in Italy, a wide number of local collapses has been observed in masonry aggregates of historical centers, highlighting the important role of local mechanisms in the seismic assessment of such structures. In this paper, an efficient software called ANUB-Aggregates (Adaptive Nurbs Upper Bound limit analysis for masonry Aggregates) is proposed for the seismic assessment of partial failure mechanisms in historical masonry aggregates. The theoretical core of this program is a kinematic NURBS-based limit analysis with meta-heuristic mesh adaptation. The use of NURBS allows studying aggregates containing vaulted structures, or any other typology of curved elements, without additional computational effort. Moreover, the mesh adaptation scheme assures the representation of the correct collapse mechanism by finding the real position of fracture lines. Starting from the three-dimensional model of the whole aggregate, the code ANUB-Aggregates provides the analysis of more macro-elements interacting with each other with different interlocking hypotheses, evaluating both simple and complex failure mechanisms. As proof of the effectiveness of this applicative, the analysis of two historical masonry aggregates is presented. [ABSTRACT FROM AUTHOR]

The seismic response and strengthening of two complex monumental masonry churches located in Northern Italy have been investigated through an advanced macro-modelling FE-based approach. An extensive documentary research and several field surveys have provided a fundamental preliminary knowledge of the two churches. Detailed three-dimensional FE models with a damage plasticity behavior for masonry have been developed and non-linear dynamic analyses have been performed to simulate the damage distribution in the churches and to identify the most vulnerable macro-elements. The analyses have highlighted the effects of geometrical features and masonry coverings on the seismic behavior of the two churches. The examination of the results in terms of tensile damage contour plots, maximum normalized displacements and energy density dissipated by tensile damage has provided a thorough description of the seismic response of both the whole church and the different macro-elements. In this regard, the procedure utilized could be regarded as a general guideline to follow for a realistic insight into the seismic response and failure analysis of large complex masonry structures without box behavior. From the results obtained, a hypothetical strengthening intervention has been implemented in the numerical models of the two churches according to the Italian Code, in order to quantitatively estimate the vulnerability reduction. A decrease of both tensile damage and displacements has been observed for the critical elements of the two churches in the case of strengthened models. Moreover, the results have shown the importance of the presence of the nave masonry covering to increase the effectiveness of the strengthening intervention, preventing the out-of-plane mechanism of the nave walls. • Failure analysis of two monumental masonry churches under seismic actions. • Identification of the critical macro-elements. • Effects of geometrical features and coverings on the seismic response. • Effectiveness of a strengthening intervention. • Strengthening implementation to reduce vulnerability on the base of the NLDAs results. [ABSTRACT FROM AUTHOR]

• Advanced numerical analysis of an historical masonry groin vault of major importance. • Detailed homogeneous 3D-FE approach with concrete damage plasticity CDP material. • Rigid body and spring RBS model with heterogeneous lateral arches. • Kinematic limit analysis KLA with few NURBS elements and progressive mesh adaptation. • Comparison with 1:5 in scale model experimentally tested and FRP reinforcement. This study presents three advanced non-linear modeling strategies for the evaluation of the non-linear behavior under horizontal loads of a historical groin vault of major importance, located in Jerusalem. The vault exhibits the typical features of the Crusaders architecture, with the masonry of the bearing structure, such as the piers and the main arches, made of big stocky stones with a high quality surface finish, and the vaults made of smaller irregular cobblestones. The first model is based on a FE Concrete Damage Plasticity (FE-CDP) macroscopic approach implemented in Abaqus, where masonry is assumed elasto-plastic with damage in both tension and compression and scarcely resistant to tensile stresses. The second model is a non-commercial Rigid Body and Spring (RBS) model, where the structure is discretized into rigid elements and elasto-plastic with softening interfaces. The arches are modeled with a heterogeneous approach, whereas the vault itself through an isotropic material with quasi zero tensile strength and softening behavior. The last model is based on Kinematic Limit Analysis with adaptive mesh and consists of few rigid infinitely resistant NURBS elements (NURBS-KLA). For validation purposes, at the University of Florence a 1:5 scale model of the groin vault was tested under horizontal loads up to collapse, also in presence of FRP reinforcement glued at the extrados after the activation of the collapse mechanism in the unreinforced case. Excellent agreement with experimental results is obtained for all the models, both in terms of load carrying capacity prediction and active failure mechanism, also in presence of FRP reinforcement. The reliability of the procedures presented is therefore demonstrated. [ABSTRACT FROM AUTHOR]

Open source projects are increasingly important in modern software development. These projects should make use of promotion channels to communicate and establish contact with users and contributors. In this article, we describe the channels used to promote a set of 100 popular GitHub projects. [ABSTRACT FROM AUTHOR]

Catalogs of refactoring have key importance in software maintenance and evolution, since developers rely on such documents to understand and perform refactoring operations. Furthermore, these catalogs constitute a reference guide for communication between practitioners since they standardize a common refactoring vocabulary. Fowler's book describes the most popular catalog of refactorings, which documents single and well‐known refactoring operations. However, sometimes, refactorings are composite transformations, that is, a sequence of refactorings is performed over a given program element. For example, a sequence of Extract Method operations (a single refactoring) can be performed over the same method, in one or in multiple commits, to simplify its implementation, therefore, leading to a Method Decomposition operation (a composite refactoring). In this paper, we propose and document a catalog with eight composite refactorings. We also implement a set of scripts to mine composite refactorings by preprocessing the results of refactoring detection tools. Using such scripts, we search for composites in a representative refactoring oracle with hundreds of confirmed single refactoring operations. Next, to complement this first study, we also search for composites in the full history of 10 well‐known open‐source projects. We characterize the detected composite refactorings, under dimensions such as size and location. We conclude by addressing the applications and implications of the proposed catalog. [ABSTRACT FROM AUTHOR]

• Earthquake response assessment of two historical masonry churches with bell tower. • FE macro-modelling approach and NLDAs to take into account dynamic interactions among different structural parts. • Seismic response, damage concentration and failure mechanism of bell towers are significantly influenced by the surrounding church walls. • Different damage evolution and patterns observed for bell towers in confined and isolated configurations. • Significant underestimation of damage levels when interaction effects with adjacent church walls are not taken into account. The earthquake response of two historical masonry churches is investigated through a finite element macro-modelling approach and non-linear dynamic analyses. The main aim of the study is to evaluate the church walls effects on the seismic performance and damage patterns of slender bell towers, which are analyzed also in the isolated configuration to perform a comprehensive comparison with the confined counterpart. The results of the numerical simulations point out that both the churches, which present different sizes, structural features and dynamic properties, are highly vulnerable to low-to-moderate seismic actions and the bell tower is one of the most critical elements, suffering widespread damage due to also the interactions effects with the neighboring church walls. The presence of shorter adjacent structural elements significantly modifies the main structural dynamic characteristics, seismic response and damage patterns of the bell tower. For both the confined towers, the first cracks originate in the connection regions with the adjacent church walls: on the other hand, for both the isolated towers, the first cracks originate mainly at the base. An advance of damage onset is also detected in the case of confined towers with respect to isolated towers. At the end of the numerical analyses, for both the case studies, the confined configurations show more remarkable damage patterns and larger values of energy density dissipated by tensile damage than the isolated ones, presenting relevant cracks concentrations mostly near the connection regions with the church walls and in the middle-upper part of the bell tower. The results of this study emphasize the paramount importance of taking into account the interactions effects with the surrounding church walls for a proper damage and failure mechanisms assessment of bell towers within the church context: simplified analyses performed on isolated configurations without considering such interaction effects may lead to significant underestimations of damage for the bell tower inside the church. [ABSTRACT FROM AUTHOR]

• Seismic response evaluation of two historical masonry aggregates. • Advanced 3D FE numerical simulations. • High vulnerability of the perimeter walls. • The structural response of a single unit is affected by the adjacent structural parts. Historical masonry aggregates represent a large portion of the cultural heritage in Italy and are highly vulnerable to seismic actions, as shown by past seismic events. Typically, they are large and complex structures for which there is a lack of knowledge and information concerning the structural behavior, in particular as far as the response to seismic actions is concerned. This paper investigates the seismic response of two complex historical masonry aggregates located in Sora (Lazio region, Central Italy), through advanced 3D FE numerical simulations. For each aggregate, a detailed 3D FE model is developed and analyzed in the non-linear dynamic range, assuming that masonry behaves as a damaging-plastic material with almost vanishing tensile strength. The seismic performance of the two aggregates is evaluated in terms of damage distribution, energy density dissipated by tensile damage and maximum normalized displacements. The numerical analyses show the high vulnerability of the perimeter walls. In particular, the units at the extremities of the aggregate are subjected to large displacements, being not efficiently braced by the adjacent units and being subjected to the torsional effects induced by the seismic action. The presence of several openings is a fundamental feature that significantly decreases the strength of the perimeter walls, influencing the damage distribution in the aggregate mainly due to out-of-plane actions. The most damaged elements are generally the walls of the tall units without lateral support and the adjacent slabs covering large spans. Numerical results also show that the structural response of a single building unit is affected by the interactions with adjacent structural parts. Moreover, it can be stated that a preliminary structural assessment through kinematic limit analysis on partial failure mechanisms may be reliable only after a proper estimation of the different structural elements playing a role in the horizontal behavior (e.g. interlocking between walls, typology of masonry, distribution of horizontal loads, constraints and dead loads distribution, etc.). The obtained results will be also used in an accompanying paper to benchmark simplified approaches that can be employed by engineers in common design practice to quickly predict the seismic vulnerability of masonry aggregates and define the most suitable strengthening interventions. [ABSTRACT FROM AUTHOR]

• The agent-based model is used to study the effects of demand's preferences, firms' innovation activities, and financial constraints on innovation projects. • The focus is on the role of green finance in the promotion of green investments. • The subsidiarity principle is explicitly considered in the modeling of a collab- orative private-public financial sector. • Green finance coupled with strong consumers' environmental quality prefer- ences leads to a more pronounced diffusion of green innovations. • Higher and faster GDP growth is achieved when a green-oriented state invest- ment bank is included in the model. The implementation of climate adaptation and mitigation policies depend on the development of green technologies whose diffusion is constrained by a number of barriers which prevent them to spread broadly and at a fast pace. By means of an agent-based computational model, the paper investigates the macro and micro economic dynamics considering the role of a "traditional" commercial bank and a state investment bank that explicitly supports green investments. Simulation results emphasize that green finance matter and that the market diffusion of environmental innovation is more pronounced when the presence of the public investment bank is combined with strong consumers' preferences oriented towards environmental quality. The relevance of the paper is twofold. Besides contributing to the literature on the finance-innovation nexus by considering the role of climate finance within a complex systems framework, it provides a model that can be used as a tool to explore policies to foster environmental innovation diffusion. [ABSTRACT FROM AUTHOR]

Abstract This paper investigates the seismic response and partial failure mechanisms of the Castle of St. George, one of the most renowned monumental constructions of the invaluable cultural heritage in Mantua (Northern Italy), which was hit by the 2012 Emilia seismic sequence. The first part of the study is based on historical analysis, documentary research, photographic collection and field surveys to achieve an accurate knowledge of the castle and a proper evaluation of the damage caused by the earthquake. All the collected information is used to create a representative and detailed finite element model of the castle and non-linear dynamic analyses are carried out using a damage plasticity model with different softening behavior in tension and compression for masonry. The finite element simulations provide additional information on the seismic response of the castle, identifying the damage patterns and the most vulnerable parts for different seismic intensity levels. The numerical results indicate that the corner towers and the vaults are the most damaged elements of the castle. The towers exhibit a severe damage concentration in the battlements, near the enlargements of the section in correspondence with the corbels and along the body near the openings. Moreover, the interaction between the tower and the adjacent walls, which are characterized by a different dynamic behavior, causes marked vertical cracks along the walls in correspondence with the connection regions. Highlights • Failure risk evaluation using advanced numerical FE computing on a historical masonry castle • Full 3D FE non-linear dynamic analyses to simulate the crack patterns observed during field surveys • Identification of the macro-elements most probably subjected to partial failure • Damage-plasticity model with softening in tension and compression for masonry • Incremental PGA analyses to investigate the PGA level needed to activate failure mechanisms [ABSTRACT FROM AUTHOR]

Abstract This paper investigates the possibility of improving the seismic performance of a small historical masonry church using fiber reinforced elastomeric isolators in bonded (BFREI) and unbonded (UFREI) applications. Detailed three-dimensional (3D) finite element (FE) models are used to characterize the behavior of the two types of FREIs. An Abaqus User Element (UEL) is developed to simulate the 3D behavior of FREIs for large scale seismic analyses of complex isolated structures. The results of cyclic shear analyses show that the proposed UEL model can accurately predict the FREIs behavior obtained through detailed 3D FE models. A series of non-linear dynamic analyses are performed to investigate the seismic response of a small historical masonry church in the original and base-isolated configurations employing both BFREIs and UFREIs. Numerical results show that the fixed-base model of the church experiences severe and widespread damage, while UFREIs are found to be effective in significantly reducing the damage level of the church when subjected to moderate-to-high seismic actions. Moreover, it can be observed that both the isolator types satisfy the maximum lateral displacement requirements reported in the literature. Highlights • Base seismic isolation of historical masonry church with elastomeric isolators. • Non-linear dynamic analyses NLADA conducted through full 3D FE models in ABAQUS. • fiber reinforced elastomeric isolators in bonded (BFREI) and unbonded (UFREI) configuration. • Abaqus User Element (UEL) to represent the 3D behavior of FREIs for global seismic analyses. • Detailed 3D FE models to characterize FREI cyclic behavior. [ABSTRACT FROM AUTHOR]

The need for seismic protection of structures located in earthquake prone areas of developing countries has motivated several investigations of low-cost seismic isolators in recent years. One of the most promising device is the Unbonded Fiber Reinforced Elastomeric Isolator (UFREI): in UFREIs no bonding or fastening is provided between the bearing and top–bottom supports and expensive thick steel plates are not required. The behavior of UFREIs is characterized by rollover and full-contact deformations under horizontal loads: the former decreases the effective stiffness of the isolation system, thus reducing the seismic demand, while the latter plays a key role in generating a hardening phase, thus limiting the horizontal displacement of the isolator under severe earthquakes. Such remarkable advantages highlight a great potential for world-wide UFREIs applications. However, until now there is no representative UFREI model available in structural analysis software codes. In this work, a comprehensive but simple UFREI model is implemented in an ABAQUS user element (UEL), taking into account non-linear, hardening and hysteretic behavior of the bearing: in addition, multiple DOFs are considered to simulate the complex 3D behavior of UFREIs, which is characterized by horizontal and vertical displacements, rotation and torsion. The effectiveness of the UEL model is evaluated performing 3D FE dynamic time history analyses on a rigid slab supported by four different types of UFREI. The results show that the UEL model can reasonably fit the behavior of the detailed FE model, significantly reducing the computational efforts of the analyses. The UEL model proposed in this study can be particularly suitable for 3D dynamic time history analyses of complex base isolated structures. [ABSTRACT FROM AUTHOR]

Carbon nano/micro-structures used as fillers in metallic lightweight alloy matrix composites are receiving considerable attention in scientific research and industrial applications. Aluminum and magnesium are the most studied light metals used as matrices in metal composites materials, principally for their low density (respectively 2.7 g/cm3 and 1.7 g/cm3) and low melting temperature (around 660 °C for both metals). A good interaction between matrix and fillers is the first step to obtain an increase in bulk properties; furthermore, the manufacturing procedure of the composite is fundamental in terms of quality of fillers dispersion. In this work the influence of surface modifications for three classes of carbon fillers for aluminum and magnesium alloy (AZ63) as matrices is studied. In particular, the selected fillers are short carbon micro fibers (SCMFs), carbon woven fabrics (CWF), and unidirectional yarn carbon fibers (UYFs). The surface modification was carried out by a direct coating of pure nickel on fibers. The electroless pure nickel plating was chosen as the coating technique and the use of hydrazine as reducing agent has prevented the co-deposition of other elements (such as P or B). Scanning electron microscope (SEM) and energy-dispersive X-ray spectroscopy (EDS) analyses were performed to study the effect of surface modifications. The mechanical properties of manufactured composites were evaluated by 4-point flexural tests according to ASTM C1161 (room temperature). Results confirm improved interactions between matrix and fillers, and the specific interaction was studied for any chosen reinforcement. [ABSTRACT FROM AUTHOR]

The recycling of waste tires is of paramount importance for environmental protection and for economic reasons. The number of scrapped tires in the United States has reached 550 million per year and is still rising. Even higher numbers are estimated in the European Union, reaching 1 billion tires per year. Disused tires create waste with a highly negative environmental impact. Tire disposal mainly involves highly polluting treatments (e.g. combustion processes to produce fuel oil), with only a small percentage of waste (3% to 15%) destined for less-invasive treatments such as powdering. In this article we will look at previous studies in which different amounts of waste tire powder are combined with cement concrete mixtures to provide a final product with mechanical properties suitable for engineering applications. Previous work has shown that a good compressive strength can be achieved through replacing 30% of powdered tire with crushed sand. First, as the percentage of aggregation between crumb rubber and crushed sand increases, compressive strength decreases. Second, aggregation replacement of crumb rubber and crushed sand shows a reduction in density at around 10%. Third, the modulus of elasticity depends on the percentages added: the more rubber added to concrete, the less elastic the product will be. In addition, a less tough concrete means higher strength. However, adding rubber to concrete increases the toughness. [ABSTRACT FROM AUTHOR]

Abstract The preservation (in terms of inhibition of failures and collapses) of architectural heritage against horizontal loads (such as earthquakes) requires an accurate assessment of the non-linear response up to failure: to this aim, the use of advanced numerical tools to perform three-dimensional non-linear dynamic analyses is fundamental. This paper investigates the performance (up to the activation of local failures and under horizontal loads) of three historical masonry palaces of the outstanding cultural heritage in Mantua (Northern Italy) after the 2012 Emilia earthquake. Despite the unquestionable importance of the three case studies, until now these palaces have not been studied with advanced numerical simulations; moreover, the recent seismic sequence and the consequent significant cracks patterns observed in the post-earthquake survey phase have pointed out their vulnerability even to small seismic actions. The first part of the study was addressed to an accurate knowledge of the three palaces, focusing especially on the information gathered during on-site surveys, bibliographical and historical research: the data collected were employed to detect the complex three-dimensional geometry of the palaces under study and to define the cracks patterns. In the second part of the study, detailed and representative three-dimensional finite element (FE) models of the structures were developed and non-linear dynamic analyses were carried out to obtain a deep numerical insight into the seismic response of the three palaces, identifying the most vulnerable elements for each structure. The comparison between the numerical results and the damage survey showed that the numerical approach used in this study may be an adequate tool to properly evaluate the seismic response of historical masonry buildings. A comparative assessment of the results obtained for the different palaces was performed in terms of predicted damage distributions, energy density dissipated by tensile damage and maximum displacements registered for the different macro-elements. Highlights • Evaluation of failure risk with advanced numerical FE computing on outstanding historical palaces • Utilization of full 3D FE Non-linear dynamic analyses NLADA method to reproduce damage • Detailed reproduction of crack patterns observed during surveys • Damage-plasticity with softening in tension and compression material used to model masonry • Incremental PGA analyses to investigate the level of PGA needed to activate failure mechanisms [ABSTRACT FROM AUTHOR]

The structural safety and seismic performance assessment of historical masonry churches belonging to cultural heritage is currently a topic of increasing interest in Italy. Recent Italian seismic events have proved that severe damage or collapse can be caused to such typology of structures even by earthquakes of small-to-moderate magnitude. This paper describes the damage occurred in three important historical masonry churches of the outstanding cultural heritage in Mantua, Northern Italy, after the 2012 Emilia earthquake and presents the results of extensive numerical investigations carried out on detailed FE models with an elasto-plastic damage constitutive law for masonry. Historical and documentary research, on-site surveys and visual inspections were fundamental to identify the critical elements and obtain a thorough detailed knowledge of the churches for the development of accurate numerical models. The results of advanced FE analyses were used to investigate the causes of the crack patterns observed after the earthquake, indicating that the damage distribution detected in the churches can be simulated satisfactorily by the numerical approach adopted. Moreover, this study provides additional information on the seismic response of the three churches analyzed under higher PGA than those registered in Mantua during the 2012 Emilia earthquake. Comparisons among the seismic response of the churches are made in terms of predicted damage distribution, maximum normalized displacements and energy density dissipated by tensile damage. [ABSTRACT FROM AUTHOR]

Abstract The Church of the Nativity in Bethlehem has a narthex in the front that is as long as the façade of the Church and about six meters wide. Currently, the narthex is covered by five cross vaults, three of which in a dangerous state of decay, and it is internally divided by three walls perpendicular to the façade, which appears to be strongly rotated outwards with a maximum horizontal top displacement of about 40 cm. Inside the central cross vault, the narthex has been heavily damaged and propped since the thirties of the last century. Numerous attempts have been made over the time to identify the causes of such damage. Some archival researches, in-situ inspections of the subsoil and detailed laser scanner surveys, which were carried out during the recent restoration works in the Church and in the narthex, allowed for gaining a deeper insight into the construction features of the cross vaults and for putting forward some hypotheses about the possible causes of damage. This paper provides a scientific validation of these hypotheses by means of finite element numerical simulations, which try to reproduce the seismic response of the Church and the deformation process of a three-dimensional simplified model of the narthex from an assumed initial configuration up to an ultimate state of damage, comparable with the current one. Such models are discretized by means of tetrahedron elements obeying a damage plasticity law that exhibits a softening behavior in both tension and compression. The numerical simulations carried out provide some results that fit reasonably with the actual deformed configuration of the narthex and can be considered as a useful tool for further insights. [ABSTRACT FROM AUTHOR]

The emerging problem of nickel allergy is increasingly widespread due to the increase in nickel content in everyday foods. The physicochemical structure of the zeolites makes it possible to adsorb nickel ions in solution. The properties of molecular sieves, together with those of a size and a chemical composition compatible with the human gastrointestinal tract, are present in a particular zeolite called clinoptilolite. In this work, a type of natural clinoptilolite was characterized before and after being subjected to two different conditioning processes with NaCl to increase its adsorption efficiency and specificity against nickel. The three forms of clinoptilolite, natural, conditioned, and biconditioned, were compared based on analysis of absolute density, X-ray diffraction pattern, granulometry, porosity, chemical composition, and grain morphology. Finally, nickel ion removal tests were performed in an aqueous solution that simulates the conditions of the gastrointestinal tract. The Ni2+ removal efficiency of natural clinoptilolite is 73.2%, while after conditioning it reaches 96.6%. Double conditioning with Na does not generate a considerable increase in removal efficiency which remains at 96.8%. [ABSTRACT FROM AUTHOR]

In Southern European countries several existing reinforced concrete (RC) buildings were designed before the introduction of modern seismic codes and thus they may be potentially vulnerable to horizontal loads. Recent seismic events have also shown that RC buildings designed without specific seismic provisions can be subjected to meaningful damages or even collapse during moderate-to-strong earthquakes. In this framework, straightforward methodologies for a preliminary and suitable seismic assessment and retrofitting of existing RC buildings are required, along with reliable and effective seismic rehabilitation techniques. In this study, a simplified displacement based procedure using non-linear static analyses is applied to obtain a preliminary estimation of the overall inadequacy of an under-designed four-storey RC frame and to propose suitable retrofitting interventions based on different rehabilitation strategies. To this aim, accurate numerical models are developed to simulate the seismic response of the RC frame in the original and retrofitted configurations. The effectiveness of three different retrofitting solutions countering the main structural deficiencies of the RC frame is evaluated through the displacement based approach. Then, non-linear dynamic analyses are carried out to assess and compare the seismic performance of the RC frame in the original and retrofitted configurations. A combined use of different approaches may represent a valuable tool to accurately address the retrofitting interventions and to assess their effectiveness in order to reduce the seismic vulnerability of poorly designed RC buildings. [ABSTRACT FROM AUTHOR]

Historical masonry structures are often located in earthquake-prone regions and the majority of them are considered to be seismically vulnerable and unsafe. Historical masonry towers are slender structures that exhibit unique architectural features and may present many inadequacies in terms of seismic performance. The seismic protection of such typologies of structures and the design of effective retrofitting interventions require a deep understanding of their behavior under horizontal loads. This paper presents the results of the seismic performance evaluation of historical masonry towers located in Northern Italy. A large set of case studies is considered, comprising a significant number of towers with high slenderness and marked inclination. First, a preliminary assessment of the dynamic behavior of the different towers is carried out through eigenfrequency analyses. Then, non-linear dynamic simulations are performed using a real accelerogram with different peak ground accelerations. A damage plasticity material model, exhibiting softening in both tension and compression, is adopted for masonry. The huge amount of results obtained from the non-linear dynamic simulations allows a comparative analysis of the towers to be performed in order to assess their seismic vulnerability and to show the dependence of their structural behavior on some geometrical characteristics, such as slenderness, inclination, and presence of openings and belfry. The evaluation of different response parameters and the examination of tensile damage distributions show the high vulnerability of historical masonry towers under horizontal loads, mainly in the presence of marked inclination and high slenderness. Some general trends of the seismic behavior of the towers are deduced as a function of the main typological features. [ABSTRACT FROM AUTHOR]

The structural assessment of historical buildings is a complex and articulated problem based on different activities. This paper describes the different phases of an integrated approach to obtain an accurate knowledge of the structural damage and seismic performance of two masonry Baroque churches located in Northern Italy and hit by the 2012 Emilia earthquake. The activities involved historical research, laser scanning survey, diagnostic investigation and structural analysis. The historical research, based on the analysis of written documents and historical maps, aimed at understanding previous structural problems and major changes in the structure over the centuries. The geometrical survey of the churches was performed by means of a laser scanner technique in order to very precisely determine the geometry of the two churches. Experimental tests and visual inspections allowed identifying location and extent of cracks, construction techniques, presence of voids and defects in structural masonry walls, as well as some characteristics of masonry. Based on this information, detailed three-dimensional finite element models of the two churches were developed and non-linear dynamic analyses were performed. The numerical simulations led to the determination of damage distribution and the identification of the most vulnerable elements, highlighting the main structural deficiencies of the churches when subjected to different levels of seismic actions. [ABSTRACT FROM AUTHOR]

JavaScript is the most popular programming language for the Web. Although the language is prototype-based, developers can emulate class-based abstractions in JavaScript to master the increasing complexity of their applications. Identifying classes in legacy JavaScript code can support these developers at least in the following activities: (1) program comprehension; (2) migration to the new JavaScript syntax that supports classes; and (3) implementation of supporting tools, including IDEs with class-based views and reverse engineering tools. In this paper, we propose a strategy to detect class-based abstractions in the source code of legacy JavaScript systems. We report on a large and in-depth study to understand how class emulation is employed, using a dataset of 918 JavaScript applications available on GitHub. We found that almost 70% of the JavaScript systems we study make some usage of classes. We also performed a field study with the main developers of 60 popular JavaScript systems to validate our findings. The overall results range from 97% to 100% for precision, from 70% to 89% for recall, and from 82% to 94% for F-score. [ABSTRACT FROM AUTHOR]

The architectural heritage was severely damaged by the seismic sequence that occurred in Emilia (Northern Italy) in May 2012. This paper investigates the seismic behavior of three masonry churches that were damaged by the 2012 Emilia earthquake. The analyzed churches are located in the South-East area of the province of Mantua: they are representative of some churches, denoted as 'Matildic churches', belonging to the territorial area between Lombardia, Emilia Romagna and Toscana and built during the Matilde di Canossa domain, between the X and the XI centuries. The study was based on detailed field surveys, in situ tests, visual inspections and existing archives in order to obtain an accurate knowledge of the churches and a proper evaluation of the damage caused by the earthquake. Then, detailed finite element models of the churches were developed and non-linear dynamic analyses with different peak ground accelerations were performed. The numerical simulations provided a deep insight into the seismic behavior of the analyzed churches, identifying the damage patterns and the main collapse mechanisms for different seismic intensity levels. The obtained results appear to be in a good agreement with the damage experienced by the churches during the earthquake. This study can be considered as a first step to assess the seismic vulnerability of the 'Matildic churches', extremely important for their historical and architectural value. [ABSTRACT FROM AUTHOR]

The aim of this work is to introduce recycled paper in HDPE matrix composites, an interesting alternative to traditional recycling process for paper. This strategy allows both re-using paper and reducing the amount of virgin polymer used in the same volume. For this application, the recycled paper goes through a micronization process, which uses simultaneously the action of impact and friction. The production of the composite is realized either by traditional injection moulding or by turbomixing. The best fibres' dispersion was obtained by turbomixing and the composites produced in this way have been additivated with maleated polyethylene (MAPE) in the amounts of 1, 3 and 5 wt%. The resulting composites with 10 wt% fibres were characterized from the morphological and mechanical point of view. Tensile tests revealed a rather constant stiffness and some improvement of strength with respect to the neat matrix, also indicating that the best results were obtained by the addition of 1 wt% MAPE. SEM micrographs evidenced that, in the absence of additive, fibre-matrix interface was rather weak. In addition, the samples with added MAPE appear to experience a reduction in microporosity, which was confirmed also by water absorption test. [ABSTRACT FROM AUTHOR]

This study presents the main results of the numerical investigations carried out on an innovative repairable fuse device for dissipative beam-to-column connections in moment-resisting composite steel frames. The fuse consists of steel plates bolted to the web and bottom flange of the beam with a specifically detailed gap in the concrete slab. The behavior of the fuse device is studied by means of two different numerical approaches. Numerical analyses performed on detailed three-dimensional finite element models of beam-to-column sub-assemblages show that potential damage concentrates only in the fuse section, without any significant damage in the other structural elements. Repair work, if needed, is therefore limited to the replacement of the fuses only. The effects of some geometrical characteristics of the flange plates on the behavior of the fuses are investigated. In order to extend the results of the numerical analyses to multi-storey frames subjected to seismic excitations, simple numerical models of the device are developed and calibrated through the experimental results of laboratory tests. Non-linear dynamic and static analyses are performed on multi-storey composite steel frames and the effectiveness of the fuse devices is evaluated. The influence of the main mechanical characteristics of the different devices on the seismic performance of several composite steel frames is also discussed for various ground motion intensity levels. Experimental and numerical results show that it is possible to successfully dissipate energy and concentrate plasticity by means of the fuse system, along with simple and cost effective repairability. [ABSTRACT FROM AUTHOR]

An innovative repairable fuse device for moment-resisting composite steel frames is numerically investigated in this study developed within the European research project “Fuseis”. The fuse device consists of steel plates welded to the web and bottom flange of the beam with a specifically detailed gap in the concrete slab. In case of damage after a severe seismic event, the repair work is limited only to the replacement of the fuse. The results of preliminary numerical analyses carried out on detailed finite element models of beam-to-column sub-assemblages show that the dissipative fuses are able to concentrate plastic deformations in the steel plates protecting the other structural elements. Parametric investigations are performed to examine the influence of some relevant geometric characteristics of the flange plate on the fuse behavior. Then, a simplified numerical model of the device is developed and calibrated using the results of experimental tests carried out on beam-to-column sub-assemblages. The effects of the application of the device on the seismic performance of multi-storey composite steel frames are investigated through non-linear dynamic and static analyses. The results of the numerical analyses show the effectiveness of the fuse devices to dissipate large amounts of plastic energy and to preserve the other structural elements from damage. The influence of both the main mechanical characteristics and different locations of the fuses is also discussed in terms of relative seismic performance of the composite steel frames under study. [ABSTRACT FROM AUTHOR]

In this paper a masonry baroque church by Antonio Galli Bibiena in Villa Pasquali is analyzed using a multidisciplinary approach. The importance of this monument is due to the prestige of its architect and to the peculiar system of masonry perforated vaults, which is an unicum in architectural history. Nevertheless, until now this church has not been studied, but historical data and significant crack patterns have pointed out its high vulnerability. The first step related to the knowledge of the building consists of the historical record of archival documents, which allow for the identification of the vulnerable elements. An accurate geometric survey is carried out with Terrestrial Laser Scanning in order to detect the complex three-dimensional geometry of the structure and crack patterns. Finally, a three-dimensional finite element model of the entire structure is developed and a comparison between the numerical results and the damage survey is performed. [ABSTRACT FROM AUTHOR]

This paper investigates and compares the seismic performance of two types of innovative repairable fuse devices for earthquake resistant composite steel frames through experimental tests and numerical analyses. The fuses are energy dissipating devices consisting of steel plates that can be welded or bolted to the beam web and bottom flange. The numerical analyses performed in this study are based on the results of experimental tests carried out on beam-to-column sub-assemblages equipped with both the types of fuse devices. The main differences in terms of hysteretic behavior and failure modes of the fuses are identified through the experimental campaign. Detailed three-dimensional finite element models of the beam-to-column sub-assemblages are then created to provide a deeper insight into both the response and the effectiveness of the two investigated devices. On the basis of the results of both the experimental tests and numerical analyses, simplified models of different types of fuses are developed in order to study the effects of bolted and welded devices on the seismic response of composite steel frames. The results are then extended to the case of three-dimensional building structures with different number of storeys. The experimental and numerical investigations prove the effectiveness of the fuses and highlight the main differences between the two possible solutions. [ABSTRACT FROM AUTHOR]

We study the relation between variety, market concentration, and economic growth, along different phases of economic development which entail a number of changes to the structure of production and consumption in the economy. We focus on three aspects of structural change, which are connected and are correlated to variety, market concentration, and economic growth: (i) product quality; (ii) firms’ mark-ups; and (iii) imitation of consumer preferences for price and quality. We model the interactions among several aspects of structural change such as firm size and hierarchical structure, innovation in capital vintages, the emergence of social classes, income distribution, and consumer preferences across and within classes. We find that market concentration has a significant and positive impact on economic growth only in the presence of sufficiently large demand. The strongest effects emerge in the presence of a more skewed firm size distribution and firms producing higher priced and higher quality goods. We find also that this effect is influenced strongly by different aspects of structural change. Changes in the behaviour (or income) of the less wealthy income classes is crucial as is investment in new capital vintages, and the emergence of diverse income classes with heterogeneous consumption preferences. In contrast, we find that supply side product variety, cœteris paribus , has no significant effect on growth. [ABSTRACT FROM AUTHOR]

The behavior of eight historical masonry towers, located in the North-East region of Italy, is analyzed under horizontal loads by means of detailed 3D FE models. The geometry of the towers is deduced from both existing available documentation and in-situ surveys. The towers, albeit unique for geometric and architectural features, show some affinities that justify a comparative analysis, as for instance the location and the similar masonry material. Their structural behavior under horizontal loads is therefore influenced by geometrical issues, such as slenderness, walls thickness, openings, presence of internal vaults and irregularities. Non-linear dynamic analyses are performed on detailed 3D FE models of the towers using a real accelerogram with different peak ground accelerations. A damage plasticity material model, exhibiting softening in both tension and compression, is used for masonry. Non-linear dynamic simulations show the high vulnerability of ancient masonry towers under horizontal loads. Numerical results are then compared with a non-linear static procedure based on pushover analyses in terms of displacement demand and tensile damage distribution. It is found that the results obtained with the non-linear static procedure are in a good agreement with those obtained through more time-consuming non-linear dynamic simulations, with a slight less conservative trend. [ABSTRACT FROM AUTHOR]

The seismic vulnerability assessment of eight historical masonry towers, located in the North-East region of Italy, is carried out by means of simplified approaches. Three-dimensional finite element models of the eight towers are created on the basis of geometrical data deduced from both existing available documentation and insitu surveys. First, preliminary eigen-frequency analyses are performed in order to obtain some basic information about the structural behavior of the different towers. Then, a simplified approach based on non-linear static pushover analyses is adopted for the seismic verification of the global performance of the eight towers. In order to avoid unnecessary complications due to the utilization of orthotropic damaging models requiring many material parameters, a damage plasticity approach is used for masonry. The essential aspects of the masonry material are reproduced with sufficient care, namely the very low tensile strength, damage in tension and crack-crushing in compression. From an overall analysis of the results, it can be observed that almost all the towers are able to resist the seismic action corresponding to Sa g = 0.1 g, whereas the majority are unsafe at least along one geometric direction for Sa g = 0.2 g. Finally, this study presents the evaluation of the seismic safety Index by means of the simplified sectional approach suggested by Italian Guidelines on Cultural Heritage. The collapse accelerations for the towers under consideration are compared and it is found that the results obtained with the different approaches are in a good agreement with a slight conservative trend for the simplified procedure proposed by Italian Guidelines. [ABSTRACT FROM AUTHOR]

This study presents a detailed failure analysis of seven masonry churches, which were severely damaged during the 2012 Emilia-Romagna (Italy) seismic sequence, by means of 3D FE non-linear dynamic simulations. The main aims of the numerical investigations are: (1) to carry out a sufficiently wide sensitivity study on different specific case studies to have an insight into the role played by the geometry – which is always unique for churches – and by the irregularities; (2) to validate or address the limits of applicability of the most widespread conventional static approaches recommended by Italian Code, i.e. kinematic limit and pushover analyses. Non-linear dynamic analyses are carried out assuming that masonry behaves as a non-linear material exhibiting softening and damage, frictional behavior and different strength in tension and compression. The set of case studies investigated in this work shows how conventional static approaches are still capable of roughly identifying the most critical macro-elements that usually activate a failure mechanism, but that the results (e.g. collapse acceleration, behavior factor) are affected by a level of approximation that may considerably depend on in-plan irregularity and hypotheses done on the interlocking between contiguous walls. From the comparative analyses carried out, it is authors’ opinion that it is always beneficial to perform different types of analysis in order to have a comprehensive insight into the portions of the structure that can suffer a partial collapse with high probability. Once the active mechanism is identified, non-linear dynamic analyses, with more sophisticated material models and with refined FE discretizations of the critical regions, may be useful to deepen the knowledge of the behavior of such complex structures under seismic actions. [ABSTRACT FROM AUTHOR]

In case of a mass casualty radiation event, there is a need to distinguish total-body irradiation (TBI) and partial-body irradiation (PBI) to concentrate overwhelmed medical resources to the individuals that would develop an acute radiation syndrome (ARS) and need hematologic support (i.e., mostly TBI victims). To improve the identification and medical care of TBI versus PBI individuals, reliable biomarkers of exposure could be very useful. To investigate this issue, pairs of baboons (n = 18) were exposed to different situations of TBI and PBI corresponding to an equivalent of either 5 Gy 60Co gamma irradiation (5 Gy TBI; 7.5 Gy left hemibody/2.5 right hemibody TBI; 5.55 Gy 90% PBI; 6.25 Gy 80% PBI; 10 Gy 50% PBI, 15 Gy 30% PBI) or 2.5 Gy (2.5 Gy TBI; 5 Gy 50% PBI). More than fifty parameters were evaluated before and after irradiation at several time points up to 200 days. A partial least square discriminant analysis showed a good distinction of TBI from PBI situations that were equivalent to 5 Gy. Furthermore, all the animals were pooled in two groups, TBI (n = 6) and PBI (n = 12), for comparison using a logistic regression and a non parametric statistical test. Nine plasmatic biochemical markers and most of hematological parameters turned out to discriminate between TBI and PBI animals during the prodromal phase and the manifest illness phase. The most significant biomarkers were aspartate aminotransferase, creatine kinase, lactico dehydrogenase, urea, Flt3-ligand, iron, C-reactive protein, absolute neutrophil count and neutrophil-to-lymphocyte ratio for the early period, and Flt3-ligand, iron, platelet count, hemoglobin, monocyte count, absolute neutrophil count and neutrophil-to-lymphocyte ratio for the ARS phase. These results suggest that heterogeneity could be distinguished within a range of 2.5 to 5 Gy TBI. [ABSTRACT FROM AUTHOR]

Recent earthquakes have highlighted that historical fortified masonry constructions may suffer extensive damage, even under low-to-moderate seismic actions, and corner towers may be one of the most vulnerable structural elements. An accurate assessment of the structural seismic performance is one of the most effective tools to deeply understand and identify the main structural weaknesses of such a building typology. To this aim, the need to properly simulate the dynamic behavior of large complex masonry buildings can strongly limit the application of simplified analysis methods widely used in common practice and largely presented in the literature. The objective of this study is to provide a comprehensive numerical insight into the earthquake response and seismic vulnerability of historical fortified masonry palaces with corner towers using non-linear dynamic analyses and a macro-modelling FE-based approach, which is able to take into account the complex interactions between different macro-elements and the characteristics of the seismic action. After a knowledge phase of the geometrical and constructive features of the two palaces under study, detailed three-dimensional FE models have been developed and predictive non-linear dynamic analyses have been performed to assess damage patterns and identify the most critical macro-elements. The numerical analyses highlight that the seismic response and damage distributions are significantly influenced by the geometrical features and main dynamic properties of the two palaces. A fundamental role is also played by the interactions of the different macro-elements with the adjacent structural parts. The results of the non-linear dynamic analyses point out that the two palaces are highly vulnerable to seismic actions, highlighting the onset of possible local collapse mechanisms and recurrent damage concentrations. For both the palaces, the most critical elements are the corner towers that present remarkable cracks patterns along the height, in the connection regions with the adjacent walls, in the upper part and in the vaults. Widespread damage is also observed in the macro-elements that are characterized by high slenderness, large openings and small walls thickness, and in the large vaults of the two palaces. A clear correlation between large displacements and high values of energy density dissipated by tensile damage is generally observed for the main critical macro-elements of both the palaces. The main outcomes presented in this study may also represent a useful insight to improve the knowledge and better understand the earthquake response and seismic vulnerability of similar historical fortified masonry palaces located in the same region, providing valuable information for practical applications in seismic risk assessment and mitigation at territorial scale. [ABSTRACT FROM AUTHOR]

Low carbon or near-zero carbon concrete technology is in line with the pillars of sustainable development, where industrial waste or low-carbon binders can reduce or eliminate consumption of Portland cement and natural resources, leading to less environmental pollution. This work presents an experimental study on the comparison between alkali-activated materials (also recognized as geopolymers) and a traditional cementitious matrix (Portland cement) incorporated with rubber particles, deriving from end-of-life tires, as replacement of raw mineral aggregates. To explore the potential of rubber-geopolymer compounds, an experimental comparative analysis with rubber-Portland mortars was performed. Initial investigations (microstructural/compositional analysis, porosity and water absorption measurements, and mechanical tests) were conducted on rubberized samples obtained by varying the binder, the sand-rubber replacement ratio (0 vol%, 50 vol%, and 100 vol%) and the rubber particle size (0–1 mm rubber fine aggregate and 1–3 mm rubber granules). The results revealed a greater compatibility of the alkali-activated matrix with tire rubber aggregates, resulting in better performance in terms of interfacial adhesion, reduced porosity rate, flexural strength, and toughness. However, compressive strength results showed a weaker mechanical performance of rubber-geopolymer mixes compared to Portland counterparts. As also verified by Si/Al elemental analysis, the structural quality and mechanical development of the geopolymer matrix was strongly influenced by the removal of sand as a Si-source. The potential embodied carbon emission performance and cost analysis were also estimated to evaluate the economic and environmental impact related to the use of recycled rubber as complete aggregate in Portland and geopolymer mixes. Sustainability analysis revealed the greater environmental friendliness of geopolymer formulations compared to those in ordinary cement, but higher production costs. The total addition of rubber aggregates induced an increase in emissions and costs (variable according to the type of matrix) which, however, does not directly correlate with the processing/price of the polymer fraction. Deepening the research on cleaner matrices and promoting the use of recycled materials in concrete applications could lead to a gap levelling between Portland and geopolymer rubber-based composites. Building on these findings, future study will focus on the optimization of the mix design as a function of rubber aggregates. [ABSTRACT FROM AUTHOR]

The use of waste materials as alternative aggregates in cementitious mixtures is one of the most investigated practices to enhance eco-sustainability in the civil and construction sectors. For specific applications, these secondary raw materials can ensure adequate technological performance, minimizing the exploitation of natural resources and encouraging the circular disposal of industrial or municipal waste. Aiming to design and develop lightweight paving blocks for pedestrian or very light-traffic purposes (parking area, garage, sidewalk, or sports surfaces), this paper presents the material characterization of rubberized cement mortars using ground waste tire rubber (0–1 mm rubber powder and 1–3 mm rubber granules) to totally replace the mineral aggregates. Considering recommended requirements for concrete paving members in terms of mechanical strength, water drainage performance, acoustic attenuation, and dynamic and energy absorption behavior, a comprehensive laboratory testing is proposed for five different formulations varying the sand-rubber replacement level and the proportion ratio between the two rubber fractions. Tests highlighted positive and promising results to convert laboratory samples into pre-cast members. The "hot" finding of the work was to prove the feasibility of obtaining totally rubberized mortars (0 v/v% of sand) with suitable engineering performance and enhanced eco-friendly features. [ABSTRACT FROM AUTHOR]

• Seismic assessment and earthquake response of slender historical masonry bell towers. • Seismic response is affected by the main geometrical features and main vibration properties of the bell towers. • Damage distribution among the different parts of the bell towers for different PGA values. • Influence of different accelerograms on the energy density dissipated by tensile damage and maximum top displacements. • Main limitations of the simplified approach are highlighted through a comparison with non-linear dynamic analyses. Masonry bell towers represent a large portion of the Italian cultural heritage and are highly vulnerable to seismic actions mainly due to their relevant slenderness, as also observed in recent seismic events. The present study investigates the seismic vulnerability and earthquake response of five slender historical masonry bell towers, which are located in South-East Lombardia (Northern Italy), through a preliminary simplified procedure suggested by the Italian Code and advanced numerical simulations. To thoroughly study the seismic response of the bell towers, detailed three-dimensional FE models with a damage plasticity constitutive law for masonry are developed and non-linear dynamic analyses are performed using different accelerograms. The results of the non-linear dynamic analyses show that the geometrical features and the main vibration properties of the bell towers turn out to be the main parameters influencing the seismic performance of such a construction typology. Moreover, it can be noted a clear influence of the accelerograms characteristics on both the energy dissipated by tensile damage and the maximum normalized displacements of the bell towers. On the other hand, the structural geometrical characteristics play a very important role in terms of damage distribution among the different parts of the bell towers. In addition, the main limitations of the simplified approach suggested by the Italian Code for the seismic assessment of the bell towers under study are highlighted through a comparison with the results obtained from non-linear dynamic analyses. The main outcomes presented in this study may also represent a useful insight to better understand the earthquake response and seismic vulnerability of similar masonry bell towers located in the same region, providing valuable information that can be directly used in seismic risk assessment at regional scale. [ABSTRACT FROM AUTHOR]

Abstract: In this paper we present an evolutionary simulation model of industry dynamics with product innovation and differentiated demand in complex product industries, i.e. industries where products are made of many components, possibly belonging to different technologies, and providing a variety of services to consumers who have heterogeneous preferences. We analyze how the complexity of the product space, the strategies that firms follow to search this space either innovating or imitating, and the differentiation of consumers’ preference interact to determine the structure and evolutions of the industry. [Copyright &y& Elsevier]

This work aims to synthesize biocompatible composite materials loaded with recycled porcine bone powder (BP) to fabricate scaffolds for in-situ reconstruction of bone structures. Polylactic acid (PLA) and poly(ε-caprolactone) (PCL) were tested as matrices in percentages from 40 wt% to 80 wt%. Chitosan (CS) was selected for its antibacterial properties, in the amount from 5 wt% to 15 wt%, and BP from 20 wt% to 50 wt% as active filler to promote osseointegration. In this preliminary investigation, samples have been produced by solvent casting to introduce the highest possible percentage of fillers. PCL has been chosen as a matrix due to its greater ability to incorporate fillers, ensuring their adequate dispersion and lower working temperatures compared to PLA. Tensile tests demonstrated strength properties (6–10 MPa) suitable for hard tissue engineering applications. Based on the different findings (integration of PLA in the composite system, improvements in CS adhesion and mechanical properties), the authors supposed an optimization of the synthesis process, focused on the possible implementation of the electrospinning technique to develop PCL-BP composites reinforced with PLA-CS microfibers. Finally, biological tests were conducted to evaluate the antibacterial activity of CS, demonstrating the applicability of the materials for the biomedical field. [ABSTRACT FROM AUTHOR]

In the direction of reducing greenhouse emissions and energy consumption related to the activities of the cement and concrete industry, the increasingly popular concept of eco-sustainability is leading to the development and optimization of new technologies and low impact construction materials. In this respect, geopolymers are spreading more and more in the cementitious materials field, exhibiting technological properties that are highly competitive to conventional Portland concrete mixes. In this paper, the mix design, mechanical properties, microstructural features, and mineralogical properties of geopolymer mixes are discussed, investigating the influence of the main synthesis parameters (curing regime, type of precursors, activator molarity, mix design) on the performance of the final product. Moreover, recent developments of geopolymer technology based on the integration of functional nanofillers are reported. The novelty of the manuscript is to provide a detailed collection of past and recent comparative studies between geopolymers and ordinary Portland concrete mixes in terms of strength properties, durability, fire resistance, and environmental impact by LCA analysis, intending to evaluate the advantages and limitations of this technology and direct research towards a targeted optimization of the material. [ABSTRACT FROM AUTHOR]

Abstract: Schelling [Schelling, T., 1969. Models of segregation. American Economic Review 59, 488–493; Schelling, T., 1971a. Dynamic models of segregation. Journal of Mathematical Sociology 1, 143–186; Schelling, T., 1971b. On the ecology of micromotives. The Public Interest 25, 61–98; Schelling, T., 1978. Micromotives and Macrobehavior. W.W. Norton and Company, New York] considered a model with individual agents who only care about the types of people living in their own local neighborhood. The spatial structure was represented by a one- or two-dimensional lattice. Schelling showed that an integrated society will generally unravel into a rather segregated one even though no individual agent strictly prefers this. We generalize this spatial proximity model to a proximity model of segregation, examining models with individual agents who interact ‘locally’ in a range of more general social network structures. The levels of segregation attained are in line with those reached in the lattice-based spatial proximity model. [Copyright &y& Elsevier]