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Mortar-based composites are an emerging technology for the repair and strengthening of reinforced concrete and masonry structures. In most cases, the effectiveness of the retrofitting work relies on the substrate-to-composite bond capacity but in some applications, connectors are also used to prevent debonding and improve the performance of the retrofitted structure. Indeed, the use of connectors is recommended by design guidelines and suppliers are required to test them for acceptance. The paper presents a laboratory investigation on steel reinforced grout connectors, made by rolling ultra-high tensile strength steel textiles, comprising either galvanized or stainless-steel micro cords. Tensile tests were first carried out for mechanical characterization. Pull-out tests were then performed on connectors installed in holes drilled in wall panels and injected with either cement or lime mortars. Concrete, tuff masonry, brickwork and limestone masonry were used as substrate materials. Test results are commented to analyze the effect of textile rolling on tensile response, of textile and matrix properties on pull-out strength and failure mode, as well as to highlight their significance for design purposes.

BackgroundHealthcare workers (HCW) are at increased risk of being infected with SARS-CoV-2, yet limited information is available on risk factors of infection.MethodsWe pooled data on occupational surveillance of 10,654 HCW who were tested for SARS-CoV-2 infection in six Italian centers. Information was available on demographics, job title, department of employment, source of exposure, use of personal protective equipment (PPE), and COVID-19-related symptoms. We fitted multivariable logistic regression models to calculate odds ratios (OR) and 95% confidence intervals (CI).FindingsThe prevalence of infection varied across centers and ranged from 3.0% to 22.0%, being strongly correlated with that of the respective areas. Women were at lower risk of infection compared to men. Fever, cough, dyspnea and malaise were the symptoms most strongly associated with infection, together with anosmia and ageusia. No differences in the risk of infection were detected between job titles, or working in a COVID-19 designated department. Reported contact with a patient inside or outside the workplace was a risk factor. Use of a mask was strongly protective against risk of infection as was use of gloves. The use of a mask by the source of exposure (patient or colleague) had an independent effect in reducing infection risk.

Steel Reinforced Grout (SRG) is a mortar-based composite recently developed for structural retrofitting, which provides high tensile strength with limited increase in mass and in stiffness, and whose effectiveness relies on the good interaction between steel cords and inorganic matrices. Many companies already supply SRG systems for rehabilitation activities and the scientific community has been working intensively on experimental and numerical investigations to demonstrate their effectiveness for structural applications, which also led to the inclusion of SRG in national and international standards for product qualification and design. However, a clear view of the mechanical properties of these systems is still lacking, due to their variability, which, in turn, strongly depends upon cord layout, textile architecture, and characteristics of the matrix. This paper provides an overview of the mechanical properties of SRG composites on the basis of the tests carried out at Roma Tre University and of the other experimental evidences available in the literature. The results of tensile tests on bare textiles and SRG coupons with different inorganic matrices, and of bond tests on masonry and reinforced concrete substrates are collected and the performances of the different SRG systems are compared. The influence of the mortar matrix on crack spacing, ultimate strain and tension stiffening in tensile tests is analysed. The capacity of the steel cords to ensure a proper shear transfer through interlocking within the matrix and the effect of cord density on failure mechanisms in bond tests are also discussed.

The survey of damages after recent earthquakes have shown the fragility of masonry churches against the out-of-plane overturning of the façade. This failure mechanism is currently analyzed having recourse to a rigid body model, using either limit analysis with kinematic approach, or dynamic analysis under rocking motion. However, both the aforementioned methods neglect the interaction with the lateral walls, leading to an underestimation of the effective structural capacity under seismic action. The main goal of this work is therefore to investigate the effect of the interlocking between the façade and the transversal wall and the influence of the quality of masonry in out-of-plane overturning. For this purpose, a refined model of masonry through a Discrete Element Method is developed, based on a detailed recognition of masonry units. The acceleration and displacement capacity are estimated through quasi-static pushover and pulse-based dynamic analyses and compared to those calculated for the rigid body model. The proposed methodology is then applied to a sample of three single-nave masonry churches that suffered damages during the 2009 L’Aquila, Italy earthquake.

Textile Reinforced Mortar (TRM) also known as Fabric Reinforced Cementitious Matrix (FRCM) represents a valid alternative to Fiber Reinforced Polymers (FRP) for structural strengthening. The use of inorganic matrix in place of epoxy resin produces a substantial advantage in terms of physical and chemical compatibility with the substrate, especially for application to masonry members (walls or vaults). However, the increasing use of TRM systems for repair and strengthening of masonry structures is carried out in the absence of specific rules for design and assessment. Aiming at filling this lack in regulation, a joint committee between ACI 549 and RILEM TC250 was established. Based on the experimental results and modelling approaches available in the literature, a preliminary database of the significant parameters characterizing the mechanical behaviour of TRM/FRCM systems applied to masonry vaults was collected. More precisely, the load and displacement capacity of masonry vaults strengthened with FRCM composites are put in relationship with the mechanical parameters characterizing the tensile and bond properties of the strengthening systems. In such a framework, the following relevant aspects are considered: i) the contribution of the strengthening system in terms of additional capacity of the vault with respect of the delamination phenomenon; ii) the influence of the curvature on the capacity of the reinforcement and on its bond to the substrate; iii) the comprehensive effect on the overall deformability of the strengthened structure. Based on the collected data, an analytical approach is proposed to draw up simplified design rules that can be used for application to real cases

A systematic single case study with a mixed quantitative and qualitative methodology was conducted to investigate the nonlinear dynamics of change in play profiles of a child in psychodynamic play therapy. The first aim of the study was to cluster the different features of play characteristics (i.e., descriptive, cognitive, affective, and social characteristics of play, and the defensive strategies used in play) in order to construct the different play profiles of this child, and secondly to assess the transitions between profiles over the course of treatment. It was expected that there would be an increase in critical fluctuations during the transitions between the profiles and an increase in the variability of play profiles. Results showed that the child's play characteristics clustered into eight states and three attractors. The Markov Transition Matrix showed how play profiles evolved over time. Entropy analyses comparing the first and the second half of therapy showed an increase in variability. Qualitative analyses indicated the importance of expression of the child's underlying fear, and its integration with overt anger in the generation of the new play profiles. The results indicate an increase in variability, and a destabilization of old play profiles that were used towards generating new play profiles.

Allergen extracts have been used for diagnosis and treatment of allergy for around 100 years. During the second half of 20th century, the notion increasingly gained foothold that accurate standardization of such extracts is of great importance for improvement of their quality. As a consequence, manufacturers have implemented extensive protocols for standardization and quality control. These protocols have overall IgE-binding potencies as their focus. Unfortunately, each company is using their own in-house reference materials and their own unique units to express potencies. This does not facilitate comparison of different products. During the last decades, most major allergens of relevant allergen sources have been identified and it has been established that effective immunotherapy requires certain minimum quantities of these allergens to be present in the administered maintenance dose. Therefore, the idea developed to introduce major allergens measurements into standardization protocols. Such protocols based on mass units of major allergen, quantify the active ingredients of the treatment and will at the same time allow comparison of competitor products. In 2001, an EU funded project, the CREATE project, was started to support introduction of major allergen based standardization. The aim of the project was to evaluate the use of recombinant allergens as reference materials and of ELISA assays for major allergen measurements. This paper gives an overview of the achievements of the CREATE project.

Male breast cancer is rare and accounts for 1% of all breast cancers. The authors report two cases of male breast cancer at Stage III and review the literature. A Madden mastectomy with axillary clearance was performed. Patients were given adjuvant chemotherapy and started on tamoxifen. At one year follow-up the patients are alive and free from disease. Modified radical mastectomy is the preferred surgical approach for localized disease. Adjuvant hormonal therapy with tamoxifen is recommended as first-line treatment. Adjuvant chemotherapy has a role in node-positive cancer and locally advanced disease. Men should be made more aware of the disease and multicentric clinical trials encouraged to ensure an appropriate treatment on the basis of prospectively collected data.

This work analyses the relationships among the changes in the sectoral composition of an economic system and the aggregate dynamics of employment and output, with the specific aim to thoroughly understand the process of increasing service sector shares. Starting from Baumol’s (1967, 1985) and Pasinetti’s (1984) contributions, we point out a distinction between two types of structural dynamics, which come out from the interaction of sector specific technical progress and demand patterns. The first type is characterized by a relatively higher income elasticity and demand growth in the sectors with productivity growth above the average. The employment shares of these sectors expand. The second type is characterized by a relatively higher income elasticity and demand growth in the sectors with productivity growth below the average. This structural dynamics is likely to emerge if demand is not elastic to prices and the technical change is sector specific. Under these circumstances, the subset of aggregate outcomes which implies full employment growth is particularly restricted by the need for a specific appropriate balance between sectors with different rates of productivity growth. Changes in relative prices do not guarantee sectoral proportions consistent with a full employment growth path. The identification of the two dynamics is then carried out at the empirical level too, proposing an empirical evidence which is based on the top five industrialized countries (US, UK, Ger., Fr., Italy) in 22 sectors (including services) over the period 1965-1995. The analysis of the long run sectoral elasticities and the one of the cross-sectors correlations show evidence of the second type of structural dynamics.

A probabilistic procedure based on simulation is developed for the assessment of multi-span masonry railways bridges under seismic action. Each simulation comprises a non-linear time history analysis, were the vault is modelled as a beam with 2D fibre elements and the seismic action by appropriately scaled natural accelerograms. For the treatment of uncertainties, an efficient statistic approach based on a Response Surface methodology is used in which both mechanical and geometrical parameters are considered as random variables. The procedure is applied to a nine-span masonry bridge, representative of Italian railway network.

The Serra da Capivara region is under continuing investigation over the past 30 years. In recent years, in the context of a specific research on Pleistocene human settlements, many surveys and digging were undertaken. The results are convincing as we currently certify more than five Pleistocene sequences with archaeological material and OSL and 14C dating. We present in this article three of them. Vale da Pedra Furada and Tira Peia have each delivered a chronological sequence of several layers that witness production of diversified tools with evidence of use. Sitio do Meio is a site already known for its sequence in the late Pleistocene/ early Holocene. The continuing research indicates a greater sequence beginning in the late Pleistocene with many artifacts. All evidence seems to confirm a late-Pleistocene human presence in this region of Brazil. This occupation continued throughout the Holocene, with changes in cultural assemblages that display local differences and increasingly sophisticated methods of adapting to and modifying the landscape.

An improved method for the study of copper metabolism in Wilson's disease, using a stable, rather than radioactive, copper isotope (65Cu) has recently been described. We report on the use of this method for the study of a family with two members affected by Wilson's disease.The family comprised parents and four siblings: one 20-year-old male and three females, aged 22, 17 and 5 years, respectively. The boy and the 17-year-old girl both presented with liver cirrhosis. Diagnosis of Wilson's disease was suggested by elevated liver copper content and/or low caeruloplasmin levels and Kayser-Fleischer ring.All family members were given an oral dose of 3 mg of 65Cu. Blood samples were taken at 0, 1, 2, 6, 24, 48, and 72 hours. In 4 subjects, additional blood samples were drawn at 7, 14 and 21 days after dosage. The ratio 65Cu:63Cu in serum was determined in all samples by means of Inductively Coupled Plasma Mass Spectrometry.The diagnosis of Wilson's disease was confirmed in the two symptomatic members by the unequivocal decrease observed in the 65Cu percent enrichment, which approached zero by 72 hours. In contrast, Wilson's disease could be definitely excluded in both siblings, one of whom only 5 years old, on the evidence of net secondary peaks, showing normal incorporation of 65Cu into caeruloplasmin. These findings were later confirmed by genetic analysis. Parents, who carried defective genes with different mutations, also showed different abnormalities of copper metabolism.The oral test with the stable copper isotope 65Cu is a safe, non invasive option able to exclude Wilson's disease in patients with a difficult diagnosis or in a presymptomatic stage. However, positive tests must still be confirmed by copper dosage in liver biopsies, as heterozygotes can present with severe alterations of copper metabolism, without developing symptoms of the disease. The use of this test in conjunction with genetic analysis on a larger number of heterozygous subjects may add to the understanding of the Wilson's disease defect.

The civil engineering community is acquainted with the fact that existing reinforced concrete structures require constant maintenance in order to increase their service life. Nevertheless, maintenance might be not sufficient when a change of use, which entails for an increase of the service loads, damage due to aggressive environment, or the need of withstanding natural and man-made hazards were not taken into account when the structure was designed. Fiber-reinforced composites are a suitable tool to strengthen and thus increase the capacity of the structural element without changing the original configuration and adding mass. Steel reinforced grout (SRG) is a relatively new tool in the realm of fiber-reinforced composites that consists of steel fibers embedded in a cementitious mortar. This paper presents a state-of-the art on SRG that includes a literature review and points out the effectiveness of SRG for flexural strengthening and confinement of concrete members. It also proposes a design approach to strengthen reinforced concrete beams based on the available data on flexural tests on beams, bond tests on SRG-concrete joints, and tensile tests on SRG coupons.

We introduce the fermionic ZW calculus, a string-diagrammatic language for fermionic quantum computing (FQC). After defining a fermionic circuit model, we present the basic components of the calculus, together with their interpretation, and show how the main physical gates of interest in FQC can be represented in the language. We then list our axioms, and derive some additional equations. We prove that the axioms provide a complete equational axiomatisation of the monoidal category whose objects are quantum systems of finitely many local fermionic modes, with operations that preserve or reverse the parity (number of particles mod 2) of states, and the tensor product, corresponding to the composition of two systems, as monoidal product. We achieve this through a procedure that rewrites any diagram in a normal form. We conclude by showing, as an example, how the statistics of a fermionic Mach-Zehnder interferometer can be calculated in the diagrammatic language.

The destruction of Amatrice and the surrounding villages in Central Italy after the 2016 seismic sequence was so impressive that engineers, authorities and local communities started sharing the common feeling that historical stone masonry buildings were too below current safety standards. The severe damage caused by the earthquakes led to a general distrust of traditional building techniques, leading to the conclusion that there is nothing to do but demolish and rebuild, perhaps with a false antique. Is there an alternative? Is there a way to combine safety and preservation of architectural heritage? This paper aims contributing to the understanding of the seismic behaviour of stone masonry by reproducing, through simulation on a shake table, the progressive loss of compactness of a real scale rubble masonry wall up to the ruinous collapse with the separation between the two external leaves. The laboratory simulation allowed to evaluate the decrease of the fundamental frequency with increasing damage and estimate the maximum displacement profile and the amount of cracking that the wall is able to sustain before failing. Eventually, two modelling strategies based on finite and discrete element methods were proposed and applied to verify the capability of simulating the out-of-plane seismic response and the failure mechanisms of rubble masonry.

The paper investigates the effectiveness of two-dimensional Discrete Element Method as a tool for structural analysis of arches provided with buttresses and backfill and strengthened with externally bonded reinforcement. Masonry vault and buttresses are modelled as an assembly of 2D rigid blocks interacting through non-linear contact joints, the backfill is discretized into deformable elastic-plastic triangular elements, while the reinforcement is modelled by means of truss elements bonded to the substrate through non-linear springs. A parametric analysis on the influence of material parameters and the effect of the discretization of the backfill is carried out, and the outcome of different reinforcement systems, consisting of Steel Reinforced Grout applied either at the intrados or at the extrados, are analysed. The comparison with experimental full-scale tests proved the ability of the numerical approach to capture hinges position, load bearing capability, as well as the increase in deflection and load capacity provided by the reinforcement.