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To assess the impact of coronavirus disease 2019 (COVID-19) epidemics on the prevention and care for HIV and other sexually transmitted infections at a major reference centre providing preventive and clinical services in Catalonia, Spain.We retrospectively compared anonymized clinical and laboratory data from March to December 2020 vs. 2019.Monthly clinical data on HIV preexposure and postexposure prophylaxis users and on adults with HIV infection were retrieved from the administrative hospital database. Monthly tests for HIV, hepatitis B and C, Treponema pallidum, Neisseria gonorrhoeae,and Chlamydia trachomatis, and plasma lipids and glucose were recovered from the laboratory database.There were less (↓28%, P = 0.003) but more advanced (mean CD4+ cells/μl 305 vs. 370, P 0.001) HIV infections and more gonorrhoea (↑39%, P 0.001) and chlamydia (↑37%, P 0.001) infections in 2020 vs. 2019. In people with HIV, rates of HIV RNA less than 50 copies/ml remained stable (11 vs. 11%, P = 0.147) despite less scheduled visits (↓25%, P 0.001). However, they had less antiretroviral prescription changes (↓10%, P = 0.018), worse plasma lipids [mean total cholesterol 190 vs. 185 mg/dl, P 0.001;mean low-density lipoprotein (LDL) cholesterol 114 vs. 110 mg/dl, P 0.001; mean triglycerides 136 vs. 125 mg/dl, P 0.001; mean high-density lipoprotein (HDL) cholesterol 47 vs. 48 mg/dl, P = 006], and an excess of mortality (↑264%, P = 0.006) due in great part not only to COVID-19 but also to other causes.In our setting, COVID-19 epidemics was associated with an increase in some prevalent sexually transmitted infections, with less but more advanced HIV infections, and with worse nonvirologic healthcare outcomes and higher mortality in people living with HIV.

The analytical or numerical determination of the stress intensity factor (SIF) in cracked bodies usually assumes the body to be isolated. However, in fibre-reinforced composites, the fibre, which is the main load-carrying component, is embedded in a matrix. To clarify the effect the embedding matrix has on the SIF of the fibre, we propose a 3D computational model of an orthotropic fibre embedded in an isotropic matrix, and compute the SIF using the J-integral method. A parametric analysis based on dimensionless variables explores the effect of the fibre–matrix stiffness ratio as well as the effect of the degree of elastic orthotropy of the fibre. The results show that the SIF is strongly influenced by both factors, and that the matrix reduces the SIF by limiting the crack opening.

Measles can lead to serious complications and remains an important cause of morbidity and mortality worldwide. We aimed to assess the etiological diagnosis of discarded measles cases in the context of an outbreak among a highly immunized population.We conducted a retrospective observational study of discarded measles cases from an outbreak that occurred from October 2006 to July 2007 in Catalonia. A confirmed case was defined as having a positive measles serum IgM result and/or a positive result by RT-PCR in urine and/or nasopharyngeal swab; or an epidemiological link to a confirmed case. Serum specimens were tested by a commercially available indirect-format and by an in-house capture-format measles IgM enzyme immunoassays.Testing of 89 samples discarded for measles determined the etiologies for 10 (11.2%), including 1 rubella, 3 human herpes virus 6, and 6 measles infections. Of 381 confirmed cases in the outbreak, 10% had received at least one dose of the measles-mumps-rubella vaccine versus 54% of the discarded for measles (OR=0.09: 95%CI 0.06, 0.14; p0.001).Highly sensitive surveillance systems are critical to identifying cases, responding to outbreaks and verifying progress towards measles elimination. Molecular tools for measles detection and differential diagnosis, and collection of appropriate specimens for molecular and serologic testing are essential to correctly diagnose suspected measles infection.

In this paper, the one-dimensional tensile behavior of Guadua angustifolia Kunth fibre/polypropylene (PP+GAKS) composites is modeled. The classical model of Kelly–Tyson and its Bowyer–Bader’s solution is not able to reproduce the entire stress–strain curve of the composite. An integral (In-Built) micromechanical model proposed by Isitman and Aykol, initially for synthetic fiber-reinforced composites, was applied to predict micromechanical parameters in short natural fiber composites. The proposed method integrates both the information of the experimental stress-strain curves and the morphology of the fiber bundles within the composite to estimate the interfacial shear strength (IFSS), fiber orientation efficiency factor ηFOD, fiber length efficiency factor ηFLD and critical fiber length lc. It was possible to reproduce the stress-strain curves of the PP+GAKS composite with low residual standard deviation. A methodology was applied using X-ray microtomography and digital image processing techniques for the precise extraction of the micromechanical parameters involved in the model. The results showed good agreement with the experimental data This research was funded by Universidad Politécnica Salesiana within the framework of the research project Resolution: N◦ 009-008-2021-11-11

Background and aims Recent studies have found an increase in the seroprevalence of hepatitis E virus (HEV) infection in patients with autoimmune hepatitis (AIH). We aimed to assess the prevalence of positive anti-HEV IgM and IgG, and HEV-RNA in a cohort of patients with AIH, to determine the impact of positive HEV serology on patient outcome, and to evaluate the role of hypergammaglobulinemia and positive autoantibodies in the presence of positive anti-HEV serology. Methods One hundred and five patients tested for HEV infection between 2014 and 2018 were included in the study: 50 with chronic AIH (more than 1 year on treatment), and 55 with an acute hepatitis (30 patients with acute AIH and 25 with non-AIH). Results Seroprevalence of HEV was higher in patients with acute AIH (17% vs 10% in patients with chronic AIH and 8% in patients with non-AIH). Patients with acute AIH and positive anti-HEV IgG were older (58 vs 40; P = .006), had higher IgG levels (27 g/dL vs 13 g/dL; P = .03) and antismooth muscle antibodies (ASMA) titres (1:160 vs 1:80; P = .045), and were more likely to have another autoimmune disease (60% vs 16%; P = .03). At the time of HEV testing, anti-HEV IgG positive patients had significantly higher serum IgG levels (17 g/L vs 11 g/L; P = .009), ANA (1:160 vs 1:60; P = .026) and ASMA titres (1:80 vs 1:40; P = .021). Conclusion Seroprevalence of HEV in patients with AIH in Catalonia does not differ from that of the general population. The higher HEV seroprevalence in patients with acute AIH with higher levels of gammaglobulins and high antibody titres suggest the presence of cross-reactivity between HEV and liver antigens.

The current drive for sustainability demands recyclable matrices for composite materials. Vitrimers combine thermoset properties with reprocessability, but their mechanical performance in highly loaded applications, for instance, composites for aeronautics, is still to be demonstrated. This work presents the complete mechanical characterization of a new vitrimer reinforced with carbon fiber. This vitrimer formulation consists of functional epoxy groups and a new dynamic disulfide crosslinks-based hardener. The testing campaign for the vitrimer composites encompassed tension, compression, interlaminar shear strength (ILSS), in-plane shear (IPS), open-hole tension (OHT) and compression (OHC), filled-hole compression (FHC) and interlaminar fracture toughness tests under mode I and II. Test conditions included room temperature and high temperature of 70 °C and 120 °C, respectively, after moisture saturation. Tension and flexural tests also were applied on the neat vitrimer resin. The results compared well with those obtained for current aeronautic materials manufactured by Resin Transfer Molding (RTM). The lower values observed in compression and ILSS derived from the thermoplastic veils included as a toughening material. This work demonstrates that the vitrimer formulation presented meets the requirements of current matrices for aeronautic-grade carbon-reinforced composites This work was financially supported by the EU Horizon 2020 research and innovation project AIRPOXY with grant agreement 769274 under the H2020-MG-2017-Two-Stage call. J. Costa acknowledges the support of the Spanish MICINN, through the project RTI2018-097880-B-I00

Eva Dopico,1,2 Francisco Rodriguez-Frias,3– 5 Itziar Ubillos,6 Ariadna Rando-Segura,3 Damir Garcia-Cehic,4,7 Josep Gregori,4,7 Yolanda Rando-Matos,8,9 Luis Solsona,8,9 Jordi Niubó,1,2 Juan Ignacio Esteban,4,7 Josep Costa,4,10 Miguel J Martínez,10,11 Josep Quer4,5,7 1Microbiology Department, Laboratori Clínic Territorial Metropolitana Sud, Hospital Universitari de Bellvitge, Institut Català de la Salut (ICS), Hospitalet de Llobregat, Barcelona, Spain; 2Bellvitge Biomedical Research Institute (IDIBELL), L’Hospitalet de Llobregat, Barcelona, Spain; 3Biochemistry Department, Vall d’Hebron Institut de Recerca (VHIR), Vall d’Hebron Hospital Universitari, Vall d’Hebron Barcelona Hospital Campus, Barcelona, Spain; 4Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Instituto de Salud Carlos III, Madrid, Spain; 5Biochemistry and Molecular Biology Department, Universitat Autònoma de Barcelona (UAB), Bellaterra, Spain; 6Laboratory Clínic Territorial Metropolitana Sud, Institut Català de la Salut (ICS), Hospitalet de Llobregat, Barcelona, Spain; 7Liver Diseases-Viral Hepatitis, Liver Unit, Vall d’Hebron Institut de Recerca (VHIR), Vall d’Hebron Hospital Universitari, Vall d’Hebron Barcelona Hospital Campus, Barcelona, Spain; 8Equip d’Atenció Primà ria Florida Nord, Gerència d’Àmbit d’Atenció Primà ria Metropolitana Sud, Institut Català de la Salut (ICS), Hospitalet de Llobregat, Barcelona, Spain; 9Fundació Institut Universitari per a la recerca a l’Atenció Primà ria de Salut Jordi Gol i Gurina (IDIAPJGol), Barcelona, Spain; 10Microbiology Department, Hospital Clínic, University of Barcelona, Barcelona, Spain; 11ISGlobal, Hospital Clínic - Universitat de Barcelona, Barcelona, SpainCorrespondence: Josep Quer, Liver Diseases-Viral Hepatitis, Liver Unit, Vall d’Hebron Institut de Recerca (VHIR), Vall d’Hebron Hospital Universitari, Vall d’Hebron Barcelona Hospital Campus, Barcelona, Spain, Tel +34 934894034, Email josep.quer@vhir.org Miguel J Martínez, Microbiology Department, Hospital Clínic, University of Barcelona, Barcelona, Spain, Email MYOLDI@clinic.catBackground: Hepatitis C virus (HCV) is a major cause of chronic liver infection with 71 million people infected worldwide. Pakistan has the second highest prevalence of HCV infection and more than half (52%) of Pakistani living in Spain reside in Barcelona. The aim of this study was to analyse the seroprevalence and viraemic rate and determine the genotypes and subtypes of HCV among Pakistanis living in the southern metropolitan area of Barcelona.Methods: We included all Pakistani patients seeking primary healthcare in the southern metropolitan area of Barcelona from August 2011 to July 2014. Serum samples were screened for HCV antibodies. HCV viral load was determined by reverse transcription polymerase chain reaction and genotypes and subtypes were performed using Versant HCV Genotype and/or deep-sequencing. Screening for hepatitis B virus (HBV) was also carried out.Results: Among 5877 Pakistani patients, 565 (9.61%) were screened for anti-HCV antibodies, with 68 (12.04%) being positive. The viral load was determined in 65, with 31 presenting active infection and the viraemic rate was 47.69% (95% confidence interval 36.02– 59.62). HCV genotyping and subtyping were performed in 24 individuals. Most infections corresponded to HCV genotype 3 (91.67%), and high resolution HCV subtyping was performed in 18 samples, 16 of which presented subtype 3a. One subject presented HBV coinfection with undetectable HBV DNA. During the study period, we identified a possible case of HCV vertical transmission followed by spontaneous viraemia clearance in a chronically infected mother with a C/T IL28B genetic polymorphism.Conclusion: These results suggest that general HCV screening protocols in patients from high prevalence countries, such as Pakistan, would be helpful to identify and treat active HCV infections. This could avoid further transmission and contribute to building targeted health policies for micro-elimination of HCV infection in specific communities.Keywords: hepatitis C virus, migrants, HCV genotype, HCV subtype

Longitudinal tensile failure of unidirectional fibre-reinforced composites remains difficult to predict accurately. The key underlying mechanism is the tensile failure of individual fibres. This paper objectively measured the relevant input data and performed a detailed experimental validation of blind predictions of six state-of-the-art models using high-resolution in-situ synchrotron radiation computed tomography (SRCT) measurements on two carbon fibre/epoxy composites. Models without major conservative assumptions regarding stress redistributions around fibre breaks significantly overpredicted failure strains and strengths, but predictions of models with at least one such assumption were in better agreement for those properties. Moreover, all models failed to predict fibre break (and cluster) development accurately, suggesting that it is vital to improve experimental methods to characterise accurately the in-situ strength distribution of fibres within the composites. As a result of detailed measurements of all required input parameters and advanced SRCT experiments, this paper establishes a benchmark for future research on longitudinal tensile failure The research leading to these results has been conducted in the framework of the FiBreMoD project and has received funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement No. 722626. Compressive tests on the neat epoxy resin were performed at the mechanical lab of the Institute of Mechanics, Materials and Civil Engineering (IMMC), Université Catholique de Louvain (UCLouvain) with the kind support of J. Chevalier and T. Pardoen. M.J. Emerson from QIM, Technical University of Denmark (DTU) is thankfully acknowledged for the handson training sessions and support of the Insegt Fibre segmentation toolbox. Support of C. Schlepütz from TOMCAT beamline at Swiss Light Source for optimising the acquisition settings during the beamtimes under proposal IDs 20161157 and 20171494 is thankfully acknowledged. J.M. Guerrero would like to acknowledge the grant BES-2016-078270 from the ‘Subprograma Estatal de Formación del MICINN’ cofinanced by the European Social Fund, and all authors from the University of Girona acknowledge the funding from the Spanish project RTI2018-097880-B-I00. The work of M. Hajikazemi forms part of the research programme of DPI, project 812T17. S. Pimenta acknowledges the funding from the Royal Academy of Engineering in the scope of her Research Fellowship on “Multiscale discontinuous composites for high-volume and sustainable applications” (2015-2019). R.P. Tavares and P.P. Camanho would like to thank the financial support provided by FCT - Fundação para a Ciência e a Tecnologia through National Funds in the scope of project MITP-TB/PFM/0005/2013

The mass manufacturing of composite products is hindered by long curing times, and composite manufacturers demand shorter curing cycles while keeping material properties. This requires reliable methods to predict the curing kinetics of each resin formulation. Isoconversional methods are easy to implement and able to deal with complex processes. However, scientists still limit their isoconversional predictions of curing degree to isothermal or constant heating programs. In this study, we perform combined dynamic and isothermal DSC measurements for two different commercial epoxies for aerospace applications (M18 and VTC401). Based on the isoconversional kinetic analysis, we show the feasibility of predicting the evolution of an epoxy resin cure for an arbitrary and complex temperature program using two different unexplored methods for this purpose. Because of the versatility of both prediction methods, they are especially suited to deal with actual conditions in industrial processes. The proposed approach is validated experimentally by comparing predictions against the curing degree of these epoxies during a temperature program that comprises isothermal and dynamic stages. These reliable and straightforward predictions open the door to optimize curing times and increase productivity in composites.

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Objective In 2006, a measles outbreak occurred in Catalonia (Spain), six years after endemic measles was declared eliminated. This study aimed to classify 19 confirmed measles breakthrough cases (BC) using a high-performance avidity assay developed in 2010. Methods Serum specimens were tested by indirect IgG, indirect IgM, capture IgM enzyme immunoassay, an endpoint-titer IgG avidity assay, and a plaque reduction neutralization assay. Serology and RNA detection results were combined in an algorithm for measles confirmation and classification of breakthrough cases and analyzed with clinical and epidemiological data. Results Of 19 samples, thirteen (68%) were conclusive with the classification of BCs, and six (32%) had false-positive IgM results on an indirect-format assay; they were classified as rash and fever illness of undetermined etiology. BCs were primary vaccine failures (seven or 54%), secondary vaccine failures (four or 31%), and two (15%) could not be classified. Conclusions In measles elimination settings, high-performing assays and a comprehensive algorithm of laboratory results (IgG, IgM, and RNA detection), including IgG avidity and PRN results when necessary, can assist in accurate laboratory confirmation and classification of suspected measles cases for surveillance. Highly specific IgM assays are required to minimize the number of false-positive results.

Background: Severe cases of primary HIV infection have been described in patients presenting with neurological involvement, AIDS defining events or other life-threatening events. These severe forms have not been fully studied. Objectives: To determine the prevalence and characteristics of severe PHI in a hospital-based cohort of primary HIV infection, and the response to the early initiation of antiretroviral therapy (ART) at 12 months. Methods: Every patient with PHI attending Hospital Clínic of Barcelona (1997–2015) was evaluated. Severe PHI was defined using clinical, analytical and immunological criteria. Chi-squared test was used for categorical variables and Student’s t-test for quantitative variables. Results: 33% of 224 PHI patients (95% CI: 26.84%–39.16%) had a severe PHI. These patients had more symptoms, abnormal analytical parameters and hospital admissions. The severe PHI group had a significantly higher viral load although no differences were observed at 12 months in terms of viral suppression or CD4 count recovery. None died during PHI. Conclusions: Up to one third of patients in our cohort presented with a severe PHI, which was associated with higher hospitalization rates and higher plasma HIV RNA viral load. However, severe forms were not associated to a worse clinical, immunological or virological outcome at 12 months. Keywords: Primary HIV Infection, Acute HIV Infection, Recent HIV Infection, Severity, Early antiretroviral therapy

With aeronautic industries focussing on thinner structures and reducing manufacturing costs, recent research has been dedicated to the impact and post impact response of thin laminates (

There is a lack of research available on how thin laminates respond to impact and post impact loads, even though thin structures are used in present-day aircrafts. This experimental paper employs thick, standard and thin uni-directional plies to investigate the effect ply thickness has on thin laminates on their impact and compression after impact (CAI) response. Further, we propose two hybrid laminates where thick or standard plies are mixed with thin plies, respectively, in an effort to improve the CAI strength of thin laminates. Results reveal that, contrary to thick laminates, thin laminates made of only thin plies exhibit extensive fibre failure, leading to a considerably reduced CAI strength. Moreover, the hybrid laminate where thick 0° plies are mixed with thin plies improves the CAI strength by 40% over the thin ply baseline laminate. Thus, hybridization with thin laminates appears to be an economic prospective in terms of improving damage tolerance.

Recent research has been devoted to thin laminates as a result of aeronautic industries shifting to thinner and lighter structures. In an attempt to improve the out-of-plane response and reduce manufacturing costs considerably, airplane manufacturers are exploring (apart from unidirectional tapes) textile fabrics of different fabric architectures. Within the framework of thin laminates, this paper investigates the impact and compression after impact (CAI) of two types of aerospace graded spread-tow fabrics, namely non-crimp fabrics and woven fabrics, where stitching and weaving, respectively, govern the architecture. The study also comprises two different ply thicknesses (thin and intermediate ply grades) for both fabrics. Experimental results reveal that while woven fabrics display higher damage resistance, non-crimp fabrics ensure higher damage tolerance. The intermediate ply grade performed better than thin plies in terms of damage resistance and CAI strength for both fabrics, as thin ply non-crimp fabric laminates exhibited early and extensive fibre damage.

This paper presents an analytical model to predict the stress redistribution around broken fibres in hybrid polymer composites. The model is used under the framework of a progressive failure approach to study the load redistribution around breaks in hybrid composites. The outcomes of the model are validated by comparing it with a spring element model. Moreover, the approach is further used to study the tensile behaviour of different hybrid composites. The results obtained show that the load redistribution around breaks depends on the stiffness ratio between both fibres as well as the matrix behaviour considered and the hybrid volume fraction. Furthermore, the different material parameters have a large effect on the tensile behaviour, with an increase of ductility achieved if the failure process of the two fibres is gradual.

Thin-ply composite laminates are currently receiving researchers’ attention due to their specific advantages in delaying or even suppressing some damage mechanisms such as matrix cracks. Lower load capacity during impact event is one of the main factors against thin-ply laminates use. This paper presents novel thin-ply laminate design with improved damage resistance and load capacity. First, the effect of mismatch angle on damage resistance and damage mechanisms occurring during an impact event on thin-ply composite laminates is studied by means of a series of quasi-static indentation tests and X-ray computed tomography and ultrasonic C-scan techniques. The results show that the projected delamination area in thin-ply laminates is independent of the mismatch angle. However, the different damage mechanisms and load capacity are dependent on the mismatch angle; the smaller the mismatch angle is, the higher the matrix cracking density, the lower number of delaminated interfaces, the higher fiber breakage density and higher load capacity are. Based on these results and other available in the literature, a thin-ply laminate with small mismatch angles between plies (to improve the maximum load) and clustered plies in the upper part of the laminate (to force damage growth in this part) is designed to present improved damage resistance and load capacity of thin-ply laminates. This laminate shows 38.8% lower delamination area when compared to the laminate with small mismatch angles.

Models for simulating interlaminar crack growth in composites under static and fatigue loads are rarely validated with experimental data different from simple standard tests where the crack front propagates with a uniform shape. The underlying reason for not making use of more realistic experimental data, where the crack front shape changes during the delamination growth, is the lack of well-controlled benchmark cases. This work introduces a comprehensive benchmark case consisting of a double cantilever beam (DCB)-like specimen with partially reinforced arms. A complete set of elastic and fracture properties for the material and a detailed description of load-displacement curves and crack front geometries, monitored with X-ray radiography, is provided. The benchmark case generates a rich phenomenology of crack advance in terms of varying crack growth rate and front shape, while being geometrically simple enough to be simulated.

Modern aircraft designs combine carbon–aluminium assemblies mechanically joined by steel bolts. The different thermal expansion coefficient of these materials and the substantial temperature excursions during aircraft operation, lead to thermal stresses that alter the load distribution of the bolted joint. These stresses can compromise the structural integrity of large components and they are difficult to anticipate. In this paper, we present a detailed experimental and computational study of a hybrid carbon–aluminium wingbox subcomponent. Thermal tests were performed to determine the global deformation of the assembly. The numerical model is compared against the experiments and is used to extract additional information that cannot be easily measured experimentally, for instance the evolution of the bolt preload with temperature. The agreement between the experimental results and simulation instils confidence in the proposed methodology to identify, and minimise through redesign, areas prone to damage due to the combination of thermal and mechanical loads This work was carried out under the framework of the EU H2020 Clean Sky 2 Project INNOHYBOX - Innovative solutions for metallic ribs or fittings introduced in a composite box to optimally deal with thermo-mechanical effects. This project has received funding from the Clean Sky 2 Joint Undertaking (JU) under grant agreement No. 785433 Open Access funding provided thanks to the CRUE-CSIC agreement with Elsevier

Many models for prediction of longitudinal tensile failure of unidirectional (UD) composites have been developed in the last decades. These models require significant assumptions and simplifications, but their consequences for the predictions are often not clearly understood. This paper therefore presents a blind benchmark of seven different models applied to two virtual materials. Reliably capturing the localisation of stress concentrations was vital in predicting the effect of matrix stiffness and strength on composite failure strain and strength as well as fibre break and cluster development. Although the models have different assumptions regarding stress redistributions around fibre breaks, the 2-plet (clusters of two fibre breaks) development was similar. Distance-based criteria were shown to be inadequate for monitoring cluster development. The discussions provide detailed insight into how the model assumptions are linked to the differences in the predictions. European Union’s Horizon 2020 research and innovation programme published

We performed in-situ tensile tests on two carbon fibre/epoxy composites with continuous scanning using synchrotron computed tomography (CT). Both composites were cross-ply laminates, and two specimens were tested for each compos- ite. The voxel size was sufficiently small to recognize individ- ual fibres and fibre breaks. For each test, 16-19 volumes were reconstructed, cropped down to the 0° plies and analysed to track fibre break and cluster development. This dataset provides the last CT volume before failure for each of the four specimens as well as the individual fibre break locations in all reconstructed volumes. These data are then plotted against predictions from six state-of-the-art strength models. The target is that these data become a benchmark for the development of new models, inspiring researchers to set up refined experiments and develop improved models. © 2021 Published by Elsevier Inc. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/)

A significant proportion of patients infected with SARS‐CoV‐2 develop severe respiratory symptoms due to an excessive immune response. Treatment of this condition may include immunosuppressive therapies, such as IL‐6 receptor antagonists and corticosteroids, which poses a risk for patients with active or past hepatitis B virus (HBV) infection. In this prospective cohort study we analyzed the risk of HBV reactivation in patients with severe COVID‐19 and resolved HBV infection undergoing immunosuppressive therapy. From March 15thto April 30th2020, 600 patients with severe COVID‐19 were admitted into our Hospital and treated with immune‐modulators. Data regarding HBV infection was available in 484, of whom 69 (14%) were HBsAg negative/anti‐HBc positive. For these patients, HBV reactivation prophylaxis with entecavir was strongly recommended. Complete follow‐up was available in 61 patients: 72% were male, median age was 67 years, and anti‐HBs was >10 IU/mL in 72%. The immunosuppressive drug most used was tocilizumab (72%). Despite HBV prophylaxis recommendation, 38 (62%) patients received entecavir and 23 (38%) did not. Baseline features of both groups were similar. At follow‐up, we found no cases of HBsAg seroreversion and only 2 (3%) patients (no prophylaxis group) had detectable serum HBV‐DNA (

Determining fatigue onset and crack propagation curves for delamination in composites requires time-consuming test campaigns. This work presents a new test rig and its associated methodology to test several mode I specimens simultaneously in a universal testing machine. The novelty of the solution relies on being able to test several specimens at different levels of load ratio and energy release rates in a single run. The performance of the system is exemplified by measuring the complete onset and crack growth rate curves of a batch of 12 carbon fibre reinforced specimens in only two test runs.

The definition of the specimen dimensions in mode II fracture tests of bonded joints, where large Fracture Process Zones (FPZ) occur, is still an issue to be solved. Several conditions shall be met in order to obtain propagation values in bonded joints testing; stability of the test, full FPZ formation, and avoidance of large deflections and adherend failure. This work presents a methodology that indicates the specimen dimensions needed to obtain propagation values in End Loaded Split (ELS) tests. In addition, suitable specimen dimensions for a wide range of thin bonded joints between CFRP adherends is presented, solving the issue of defining suitable specimen dimensions to test adhesives to ensure steady state propagation.

While analytical fiber fragmentation models following the global load-sharing (GLS) assumption efficiently reproduce the stress strain curves of unidirectional composites loaded in the direction of the reinforcement when the number of breaks is moderate, they completely fail to predict tensile strength. In this paper, we propose that failure takes place when a critical density of breaks, which depends entirely on the constituent properties, is reached. Therefore, we rewrite classic GLS fragmentation models in terms of the linear density of breaks. The critical number of breaks for a set of glass and carbon reinforced polymer composites is extracted from published experimental data and fitted to an empirical law, with good predictive capability. Our approach complements GLS fragmentation models because it identifies the ultimate stress, from which the stress-strain curve given by the model becomes unrealistic.

This paper presents a three-dimensional Progressive Failure Model based on the chain of bundles able to represent the stiffness loss in unidirectional composite materials loaded in the fibre direction. A representative volume element with a random distribution of fibres with their own radius is considered. Complete stress distributions around fibre breaks are obtained by associating a damage variable to the loss of stress transfer capability along the ineffective length and applying local stress concentrations. The model has been validated by comparing it against the literature results and exhibits good agreement with hybrids and non-hybrid composites. The aim of this model is to simulate the tensile response of unidirectional composite systems dominated by fibre fragmentation mechanisms using a very reduced computational effort, even for larger representative volume elements, compared to micro-mechanical finite element models.

Hybrid bolted joints, where carbon fiber reinforced polymers and metallic plates are clamped using bolts, are widely used in aircraft structures. During operation, aircraft experience extreme temperatures that can adversely affect the response of an hybrid joint. On account of the lack of understanding on this aspect, we analyzed a representative carbon-aluminum single lap shear bolted joint using a 3D numerical model. A parametric study varying the temperature, friction coefficient, bolt clamping force, bolt-hole clearance, and thickness of the metallic plate, provided insight into their effect on the stiffness stages of the mechanical response of the joint, as well as the contact evolution among the different elements. Bolt-hole clearance was one of the parameters that most influenced the joint stiffness and bolt bending. Temperature excursions induced sliding between plates and significantly altered the clamping load of the bolt, i.e., a 40% reduction and an 18% increase for a negative and positive thermal jumps, respectively. This clamping load variation entails undesirable bolt loosening or even yielding. Therefore, this work sheds light on the detrimental effects of temperature on hybrid joints, thus providing background for a safer structural design. This work has been accomplished within the framework of an ongoing EU H2020 Clean Sky 2 Project INNOHYBOX (Innovative solutions for metallic ribs or fittings introduced in a composite box to optimally deal with thermo-mechanical effects). This project has received funding from the Clean Sky 2 Joint Undertaking (JU) under grant agreement No. 785433. The JU receives support from the European Union’s Horizon 2020 research and innovation programme and the Clean Sky 2 JU members other than the Union.

Background And Aims Acute hepatitis A is transmitted mainly via the fecal-oral route and/or contaminated aliment. Furthermore, several outbreaks in the men who have sex with men (MSM) population classified hepatitis A as a sexually transmitted disease (STD). We aimed to clarify an ongoing hepatitis A outbreak in Barcelona with respect to patients’ characteristics and viral phylogenetic analysis. Methods We prospectively analyzed 46 cases of hepatitis A infection that were registered in our hospital between January and June 2017. We evaluated demographics data, risk factors, presenting symptoms, sexual orientation, comorbidities and further STD infections. The phylogenetic correlation of the current circulating viruses among them and other hepatitis A strains was assessed by sequencing of the VP1/P2A region. Results Most patients were male (44, 96%) with median age 33.5 years (range 28-50). Thirty-one (67%) were MSM and 18 (39%) required hospitalization. Molecular phylogenetic analyses revealed that all patients were infected by hepatitis A subgenotype IA strains. Moreover, current strains comprised 3 distinct clusters, previously reported in ongoing outbreaks in the United Kingdom, Berlin and Netherlands. However, these strains were phylogenetically diverse to those previously reported in Barcelona metropolitan region. Conclusions Ongoing hepatitis A outbreak in Barcelona affects primarily the MSM community and is phylogenetically linked to current hepatitis A outbreaks described in other European countries. Due to the high admission rate, these outbreaks may impact the admission pattern of referral liver units. Control measures, e.g. vaccinations programs tailored to the MSM community, must be taken to control further spreading. This article is protected by copyright. All rights reserved.

The quest for impact damage tolerant laminates by tailoring stacking sequences has led to nonconventional laminates whose ply sequences are not limited to 0, ±45 and 90°. Departing from the hypothesis that compression after impact (CAI) strength is impaired by the presence of delaminations, a ply sequence was defined by selecting the mismatch angles between plies so as to maintain a central sublaminate with no, or small, delaminations. An experimental test campaign was devoted to validate this hypothesis. To that purpose, baseline and blocked-ply laminates were included in the study. Specimens were tested under low velocity impact followed by compression according to ASTM standards. Delaminations were identified with Ultrasonic C-Scan. The results show delamination locations being successfully predetermined by controlling the mismatch angle, as well as the ensuing improvement in compressive strength retention after impact The authors acknowledge the financial support of the Spanish Ministerio de Ciencia e Innovación under the project MAT2015-69491-C3-1-R (MINECO/FEDER, UE)

Background Mumps is a vaccine-preventable disease but outbreaks have been reported in persons vaccinated with two doses of MMR vaccine. The objective was to describe the demographic features, vaccination effectiveness and genetic mumps virus diversity among laboratory-confirmed cases between 2007 and 2011 in Catalonia. Methods Cases and outbreaks of mumps notified to the notifiable diseases system of Catalonia between 2007 and 2011 retrospectively registered were included. Public health care centres provided written immunization records to regional public health staff to determine the vaccination history. Saliva and serum specimens were collected from suspected cases for laboratory-confirmation using real-time reverse-transcriptase PCR (rtRT-PCR) or serological testing. Phylogenetic analysis of the complete SH gene (316 nucleotides) and complete coding HN protein (1749 nucleotides) sequences was made. Categorical variables were compared using the Chi-square or Fisher’s tests and continuous variables using the Student test. Vaccination effectiveness by number of MMR doses was estimated using the screening method. Results During the study period, 581 confirmed cases of mumps were notified (incidence rate 1.6 cases/100,000 persons-year), of which 60% were male. Three hundred sixty-four laboratory-confirmed cases were reported, of which 44% were confirmed by rtRT-PCR. Of the 289 laboratory-confirmed cases belonging to vaccination cohorts, 33.5% (97) had received one dose of MMR vaccine and 50% (145) two doses. Based on phylogenetic analyses of 316-nucleotide and 174-nucleotide SH sequences, the viruses belonging to viral genotypes were: genotype G (126), genotype D (23), genotype H (2), genotype F (2), genotype J (1), while one remained uncharacterized. Amino acid differences were detected between circulating strains and the Jeryl Lynn vaccine strains, although the majority of amino acid substitutions were genotype-specific. Fifty-one outbreaks were notified that included 324 confirmed mumps cases. Genotype G was the most frequent genotype detected. The family (35%), secondary schools (25%) and community outbreaks (18%) were the most frequent settings. Conclusions Our study shows that genotype G viruses are the most prevalent in Catalonia. Most cases occurred in people who had received two doses of MMR, suggesting inadequate effectiveness of the Jeryl Lynn vaccine strain. The possible factors related are discussed.

In current composite design, stacking sequence symmetry around the laminate mid-plane is an unarguable constraint to avoid warpage during manufacturing. However, several load cases induce unevenly distributed stresses through the laminate thickness, such that symmetric laminates may not be the optimal solution. In this paper, we explore the damage resistance to out-of-plane low velocity impact loading of an unsymmetrical laminate with zero extension-bending coupling matrix ([B]), thereby assuring no undesired coupling deformations during mechanical or thermal loads. Using impact and quasi-static indentation tests, C-scan inspection and numerical modelling, we compare the damage pattern between an unsymmetrical laminate with ply clustering at the impacted face and a laminate with ply clustering at the non-impacted face (produced by flipping the former laminate upside down). The laminate with clusters at the impacted side exhibits better damage resistance for lower impact energies. More importantly, the location of the damage events obeys the predictions assumed when the laminate was designed, demonstrating the room for improvement by tailoring unsymmetrical laminates to particular load cases The authors would like to thank the Spanish Ministerio de Economía y Competitividad for the grant coded MAT2015-69491-C3-1-R and supported by FEDER/EU

While fibre hybrid composites result in hybrid effects and improved ductility compared to non-hybrid laminates, it is unclear how material size influences hybrid properties (i.e. the so-called ‘size effect’). This paper addresses this phenomenon in a carbon–carbon hybrid composite by means of micromechanical modelling using a progressive failure model. Results demonstrate that increasing either the length or the cross-section of the virtual Representative Volume Element (RVE) causes an earlier failure, slightly decreases ductility and significantly improves the hybrid effect. In addition, increasing the RVE volume results in a higher maximum cluster size, while the presence of ductility does not alter the magnitude of the size effects. Further, the presence of a larger hybrid effect does not necessarily translate into greater ductility.

Healthcare workers (HCW) are exposed to preventable infectious diseases, notably hepatitis B (HB). The aim of this study was to determine the immunity of HCW against hepatitis B. We made a seroprevalence study using a self-administered survey and obtained blood samples. Antibodies against the HB surface antigen (anti-HBs) and against the HB core antigen (anti-HBc) were studied. The odds ratio (OR) and 95% confidence intervals (CI) were calculated. The adjusted OR were calculated using logistic regression. Of the 644 HCW who participated (29.7% physicians, 38.7% nurses, 13.4% other clinical workers and 18.3% non-clinical workers), 46.4% were primary care workers and 53.6% hospital workers. The overall prevalence of anti-HBs was 64.4%. HCW aged25 y had a significantly higher prevalence (86.7%) than those aged 35-44 y (adjusted OR 3.40; 95% CI 1.06-10.90). The prevalence of anti-HBc was 4.1%, and increased with age. Significant differences were found for HCW aged44 y with respect to those aged 25-34 y. 75.6% of HCW stated they were vaccinated, but only 39.3% had a vaccination card. In HCW who stated they were unvaccinated, 10.8% had a vaccinated serological pattern (anti-HBc-negative and anti-HBs -positive). Written, updated vaccination records are essential to reliably determine the vaccination status.

OBJECTIVES IFN-based therapy against hepatitis C recurrence after liver transplantation (LT) has poor effectiveness and tolerability. In HIV/HCV-coinfected liver transplant recipients, the results are even poorer. Here, we report our experience using direct antiviral agents (DAAs) in 11 consecutive coinfected patients within the LT setting. METHODS Four patients with compensated cirrhosis and hepatocellular carcinoma were treated while awaiting LT and seven patients received antiviral therapy due to severe hepatitis C recurrence after LT [fibrosing cholestatic hepatitis (n = 1), fibrosis stage ≥F3 (n = 2) and decompensated cirrhosis (n = 4)]. Patients were treated with different sofosbuvir-based regimens with or without ribavirin for 12 or 24 weeks. RESULTS Sustained virological response (SVR) was achieved in all patients. Two of the four patients treated while awaiting LT reached the time of transplant with undetectable HCV-RNA that remained undetectable 12 weeks after LT, one patient had detectable HCV-RNA at the time of transplant but achieved SVR after completing 12 weeks of therapy after LT and the last patient is still on the waiting list. Seven patients with severe post-LT hepatitis C recurrence were treated within 11-120 months after LT. In these patients, viral eradication was associated with an improvement in liver function and clinical decompensation. Tolerance to antiviral therapy was good and only four patients reported mild adverse events. CONCLUSIONS IFN-free regimens are effective and well tolerated in HIV/HCV-coinfected patients within the LT setting, but more data are needed to confirm our promising results and to establish the best treatment option in this population.

Maternal pertussis vaccination is associated with higher levels of pertussis antibodies at birth. We assessed the persistence of pertussis antibodies until primary vaccination in infants whose mothers received Tdap (tetanus, diphtheria, acellular pertussis) vaccine during pregnancy. Infants were born at the Hospital Clinic of Barcelona (Spain) in November 2014. Anti-PT IgG was determined by ELISA at delivery, between the first and second month of life, and estimated at 2months of age. The study included 37 infants whose mothers received Tdap between 21 and 38weeks of gestation. Infants presented a decline in GMC of anti-PT IgG between peripartum and follow-up levels, 52.7 (95% CI 34.7-80.2) versus 7.5 (95% CI 4.2-13.3) at 2months of age (p

The analysis of large-scale fracture processes, such as those involved in the fracture of adhesive joints, falls outside the scope of Linear Elastic Fracture Mechanics (LEFM). However, experimental data produced in testing adhesive joints are usually reduced with LEFM methods. The consequent error has not yet been evaluated. In this work, an experimental characterization under pure-mode loading of an FM-300 epoxy film adhesive is presented for different adhesive and adherend thicknesses. The experimental data is analyzed using both LEFM-based and J-integral-based data reduction methods in order to study their suitability to analyze adhesive joints. LEFM-based data reduction methods are shown to entail a relevant deviation in the fracture toughness results that heavily depends on the size of the fracture process zone. It is concluded that LEFM methods are not suitable to characterize adhesive joints and that their use is restricted, at best, to the measurement of initiation values. The effect that the adhesive and the adherend thicknesses have on the fracture toughness and the R-curve of the material is studied. Adhesive and adherend thicknesses are shown to have a significant influence on the bond fracture toughness and the source of such influence is discussed The first author would like to acknowledge the FPU programgrant AP20100977 from the Spanish Ministerio de Educación,Cultura y Deporte. The authors also acknowledge the support of the Spanish government through the Ministerio de Economía y Competitividad under the contracts DPI2012-34465 and MAT2012-37552-C03-03

The wedge driven test is a valuable tool to determine the mode I fracture energy ( G Ic ) of adhesives or interfaces in composites. At first glance, the test is simple enough (introduction of a wedge into the specimen midplane to progagate a crack) to be a good alternative to the standard method, the DCB test. However, friction between the wedge and the specimen’s arms is not properly dealt in existing studies and, consequently, there is still a need for a reliable test procedure. In this work, we present a test methodology and its associated data reduction procedure to obtain G Ic . The test does not need to measure the crack length and the friction coefficient is determined as the wedge is introduced in between the specimen’s arms. The new testing methodology is validated experimentally comparing the G Ic obtained from the wedge driven and the DCB tests. A very close agreement is obtained between them.

Failure of composite laminates, in load cases where transverse shear prevail, involves shear cracks and delaminations, and yet it is unclear which damage mechanism triggers the other or how it depends on ply-thickness. Combining interrupted interlaminar shear strength tests with X-ray tomography inspections, we compared the damage sequence of [ 45 ° / 0 ° / - 45 ° / 90 ° ] ns short-beam specimens manufactured with standard- ( n = 2 ) or thin-ply ( n = 4 ) non-crimp fabrics (fibre areal weights of 134 and 67 gsm per ply). Failure manifested as a load drop in the force-displacement curve. In both materials, we associated the onset of instability to a shear crack tunnelling across the central 90 2 ° ply-cluster. The intersection of this crack with the ones developing in the adjacent layers induced a delamination which, in turn, activated the load drop. A 3D elasto-plastic model predicted that, for the same applied load, the ply-cluster of both laminates would display a similar maximum principal stress distribution. However, the thin-ply samples improved the interlaminar shear strength by 34%, evidencing the so called in-situ effect: the resistance to matrix cracking under transverse shear ( τ 23 in the local coordinates of the 90 ° plies) increases when ply-thickness is reduced.

In the quest to improve the compression after impact (CAI) strength of thin laminates, ply-hybrid laminates (where plies of different thicknesses are mixed) have been used in a previous study to mitigate the fibre failure and, consequently, improve the CAI strength. In the same study, hybrid laminates were proposed following qualitative design rules. In this paper, we systematically look for hybrid stacking sequences with improved damage tolerance by virtually testing all the laminates in a defined design space. While the laminates in the design space are made of intermediate and thick ply grades, the baseline laminate has only intermediate grade plies. Using an in-house numerical model, we virtually tested, (impact and CAI at two impact energies), all the candidate stacking sequences. The best hybrid laminates considerably improved the CAI strength over the baseline (31% and 40% improvement for the symmetric and unsymmetrical hybrid laminates, respectively). One of the best hybrid laminates was then manufactured and tested experimentally to validate the approach. Through virtual testing, this study demonstrates the benefits of using ply thickness hybrid laminates and the feasibility of optimizing the stacking sequence for impact damage tolerance.

Out-of-plane loads induce unsymmetrical damage modes in the laminate thickness direction. Consequently, the authors have recently proposed overcoming the conventional laminate symmetry constraint by designing unsymmetrical laminates with zero coupling responses. While impact damage is able to be tailored with unsymmetrical laminates, comparing them to symmetric laminates and assessing their impact damage tolerances had yet to be addressed. In this paper, we study three unsymmetrical laminates with localized ply clusters positioned at different locations (at the impacted, at the middle and at the non-impacted sides), along with a standard symmetric laminate as a baseline. Using low-velocity impact, X-ray micro-computed tomography and compression after impact (CAI), we compared the impact and post-impact responses to understand the effect local ply clusters and the delamination location have on the CAI strength. Results revealed that the unsymmetrical laminate with the ply clusters in the middle, where the dominant delaminations also occured, improved the CAI strength by a maximum of 10% when compared to the symmetric baseline. Laminates with delaminations at the outer surfaces offered lesser resistance to buckling. While our study demonstrates that symmetric laminates are not the optimal damage tolerant solution for impact load cases, it also evidences the feasibility of unsymmetrical laminates.