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Lattice and Triply-Periodic-Minimal-Surface (TPMS) structures are widely employed in different engineering disciplines, combining interesting designs with optimal mechanical properties thanks to the capabilities of Additive Manufacturing. In this framework, a technique based on filling a 3D-printed flexible structure with a shear-thickening fluid (STF) is proposed to improve the mechanical response of the resulting bi-phase composite under impact loads in the low-velocity regime up to around 3 m/s. Test data indicate that once the critical shear rate threshold for the fluid is reached, the STF-filled structure can effectively smooth the peak acceleration by 50%, decrease the penetration depth and significantly enhance the energy absorption capability by a remarkable 85%. The proposed hybrid composite paves the way to novel functional applications, exploiting the adaptive behavior of non-Newtonian fillers. To this end, a Finite-Element model is proposed to further investigate and optimize the underlying fluid-structure interaction responsible for improvement of the dynamic compressive response.

Knowledge of the effective slip strength is a crucial safety issue when a bolted connection is designed to work by friction. Even if technical standards indicate the necessary tightening torque to obtain the desired preload, experimental relationship between bolt torque and preload is required in many cases where surface and bolt conditions are uncertain. In this work, the torque–preload relationship and the effective slip factors of bolted joints operating under non-standard surface conditions, namely COR-TEN and Zn-coated plates, are determined experimentally, and compared with standard as-rolled data. Results indicate that the requirements of design standards are not always conservative, making experimental characterization of the joint necessary.

In this research, mechanical stress, static strain and deformation analyses of a cylindrical pressure vessel subjected to mechanical loads are presented. The kinematic relations are developed based on higher-order sinusoidal shear deformation theory. Thickness stretching formulation is accounted for more accurate analysis. The total transverse deflection is divided into bending, shear and thickness stretching parts in which the third term is responsible for change of deflection along the thickness direction. The axisymmetric formulations are derived through principle of virtual work. A parametric study is presented to investigate variation of stress and strain components along the thickness and longitudinal directions. To explore effect of thickness stretching model on the static results, a comparison between the present results with the available results of literature is presented. As an important output, effect of micro-scale parameter is studied on the static stress and strain distribution.

This paper presents an application of vibration analysis to the monitoring of tie-rods. An algorithm for the axial load estimation based on experimentally measured natural frequencies is introduced and its application to a case study is reported. The proposed model of a tie-rod incorporates elastic bed-type boundary conditions that represent the contact between stonework and the tie-rod. The weighed differences between experimentally and numerically determined frequencies are minimized with respect to the parameters of the model, the main being the axial load and the stiffness at the tie-rod/wall interface. Thus, the multidimensional optimization problem is solved. Results are analysed in comparison to a model with simple fixed-end boundary conditions. In addition, the analytical formulation of the problem is delivered.

Immunocompromised patients with leukemia/lymphoma often have a suboptimal response to vaccination against SARS-CoV-2 and, if infected, can develop a persistent infection.SARS-CoV-2 PCR was performed on nasopharingeal swabs and serum IgG anti-SARS-CoV-2 trimeric spike glycoprotein antibodies were measured during persistence of infection. Treatment with a combination of nirmatrelvir/ritonavir plus sotrovimab led to viral clearance in three patients with leukaemia or lymphoma with persistent SARS-CoV-2 and negative SARS-CoV-2 antibody tests. No standardized treatments for persistent infection with SARS-CoV-2 infection are available. We have reported the viral clearance in two immunocompromised patients treated with antiviral drug nirmatrelvir/ritonavir and monoclonal antibody sotrovimab. We suggest that this strategy should be tested in clinical trials to find the right strategy for a clinical problem with public health implications to SARS-CoV-2 evolution and immune escape in these sub-set of patients.

Background: A correct approach to recurrent urinary tract infections (rUTIs) is an important pillar of antimicrobial stewardship. We aim to define an Artificial Neural Network (ANN) for predicting the clinical efficacy of the empiric antimicrobial treatment in women with rUTIs., Methods: We extracted clinical and microbiological data from 1043 women. We trained an ANN on 725 patients and validated it on 318., Results: The ANN showed a sensitivity of 87.8% and specificity of 97.3% in predicting the clinical efficacy of empirical therapy. The previous use of fluoroquinolones (HR = 4.23; p = 0.008) and cephalosporins (HR = 2.81; p = 0.003) as well as the presence of Escherichia coli with resistance against cotrimoxazole (HR = 3.54; p = 0.001) have been identified as the most important variables affecting the ANN output decision predicting the fluoroquinolones-based therapy failure. A previous isolation of Escherichia coli with resistance against fosfomycin (HR = 2.67; p = 0.001) and amoxicillin-clavulanic acid (HR = 1.94; p = 0.001) seems to be the most influential variable affecting the output decision predicting the cephalosporins- and cotrimoxazole-based therapy failure. The previously mentioned Escherichia coli with resistance against cotrimoxazole (HR = 2.35; p < 0.001) and amoxicillin-clavulanic acid (HR = 3.41; p = 0.007) seems to be the most influential variable affecting the output decision predicting the fosfomycin-based therapy failure., Conclusions: ANNs seem to be an interesting tool to guide the antimicrobial choice in the management of rUTIs at the point of care.

Background: Management of recurrent urinary tract infection (rUTI) is still challenging. A better understanding of the natural history of rUTI could help us reduce antibiotic use and improve antibiotic stewardship., Objective: To describe the effect of risk identification, stratification, and counseling on the natural course of the disease in women with rUTI., Design, Setting, and Participants: A total of 373 women affected by recurrent cystitis were enrolled in this longitudinal cohort study between December 2014 and December 2019. A systematic and standardized identification of risk factors was performed., Intervention: As intervention, risk factors were treated or removed where possible. Patients with nonremovable risk factors were included in the control group. All patients were scheduled for follow-up visits every 6 mo., Outcome Measurements and Statistical Analysis: The main outcome measures were the rate of symptomatic recurrences and improvement in questionnaire results from baseline to the end of the follow-up period. Reduction of antibiotic usage was regarded as a secondary outcome measure., Results and Limitations: Finally, 353 women were analyzed: 196 in the study group and 157 in the control group. At the end of the follow-up period, a statistically significant reduction in the symptomatic recurrence rate was found between the two groups (0.9 ± 0.2 and 2.6 ± 0.5; p < 0.001), as well as in quality of life and anxiety according to mean questionnaire results: quality of life (0.88 ± 0.06 and 0.63 ± 0.09; p < 0.001) and Spielberger State-Trait Anxiety Inventory-Form Y (32.7 ± 9.3 and 47.5 ± 14.3; p < 0.001). The use of antibiotics was significantly lower in the study group: 4410 versus 9821 (p < 0.001). A limitation to consider is the lack of a randomized design for the active approach in the high-risk group., Conclusions: Identification, counseling, and removal of risk factors, where possible, are able to change the natural history of rUTI, by reducing the number of symptomatic episodes and antibiotic use and improving quality of life., Patient Summary: In this report, we analyzed a large cohort of women affected by recurrent urinary tract infections and followed for a long time period. We found that risk factor identification and counseling may change the natural history of recurrent urinary tract infections, concluding that this approach is able to reduce the number of symptomatic episodes, reduce antibiotic usage, and improve patients' quality of life., (Copyright © 2022 European Association of Urology. Published by Elsevier B.V. All rights reserved.)

Neonatal sepsis is a systemic condition characterized by haemodynamic changes and other clinical manifestations due to a presence of pathogenic microorganisms (bacteria, viruses, or fungi) in nor- mally sterile fluid that occurs in an infant younger than 90 days old. Neonatal sepsis may be divided into two types: early-onset neonatal sepsis (EOS) and late-onset neonatal sepsis (LOS). Gram-posi- tive microorganisms are the etiological agents in 62% of EOS, and in 43% of the total the identified microorganism is GBS. Gram-negative microorganisms comprise 37% of the etiological agents of EOS, of which 29% are caused by Escherichia coli. ESBL-producing Enterobacteriaceae represent a major worldwide threat among drug-resistant bacteria in both hospital and community settings. ESBLs are often located on large plasmids that also harbour genes resistant to other antimicrobial classes, resulting in multidrug-resistant isolates. Plasmid-encoded ESBLs of the CTX-M-type are increasingly reported worldwide in Gram-negative rods and now account for most of the ESBLs found in Enterobacteriaceae. We present one case of EOS by Multi Drug Resistant (MDR) and ESBL producing E. coli (CTX-M gene) in a neonate born to a mother recently immigrated from Africa. Maternal blood culture grew the same bacteria.

This study analyses the energy absorption and stiffness behaviour of 3D-printed supportless, closed-cell lattice structures. The unit cell design is bioinspired by the sea urchin morphology having organism-level biomimicry. This gives rise to an open-cell lattice structure that can be used to produce two different closed-cell structures by closing the openings with thin or thick walls, respectively. In the design phase, the focus is placed on obtaining the same relative density with all structures. The present study demonstrates that closure of the open-cell lattice structure enhances the mechanical properties without affecting the functional requirements. Thermoplastic polyurethane (TPU) is used to produce the structures via additive manufacturing (AM) using fused filament fabrication (FFF). Uniaxial compression tests are performed to understand the mechanical and functional properties of the structures. Numerical models are developed adopting an advanced material model aimed at studying the hysteretic behaviour of the hyperelastic polymer. The study strengthens design principles for closed-cell lattice structures, highlighting the fact that a thin membrane is the best morphology to enhance structural properties. The results of this study can be generalised and easily applied to applications where functional requirements are of key importance, such as in the production of lightweight midsole shoes.

Background: Trentino is an Italian province with a tourism-based economy, bordering the regions of Lombardy and Veneto, where the two earliest and largest outbreaks of COVID-19 occurred in Italy. The earliest cases in Trentino were reported in the first week of March 2020, with most of the cases occurring in the winter sport areas in the Dolomites mountain range. The number of reported cases decreased over the summer months and was followed by a second wave in the autumn and winter of 2020., Methods: we performed high-coverage Oxford Nanopore sequencing of 253 positive SARS-CoV-2 swabs collected in Trentino between March and December 2020., Results: in this work, we analyzed genome sequences to trace the routes through which the virus entered the area, and assessed whether the autumnal resurgence could be attributed to lineages persisting undetected during summer, or as a consequence of new introductions., Conclusions: Comparing the draft genomes analyzed with a large selection of European sequences retrieved from GISAID we found that multiple introductions of the virus occurred at the early stage of the epidemics; the two epidemic waves were unrelated; the second wave was due to reintroductions of the virus in summer when traveling restrictions were uplifted.

Efficient, wide-scale testing for SARS-CoV-2 is crucial for monitoring the incidence of the infection in the community. The gold standard for COVID-19 diagnosis is the molecular analysis of epithelial secretions from the upper respiratory system captured by nasopharyngeal (NP) or oropharyngeal swabs. Given the ease of collection, saliva has been proposed as a possible substitute to support testing at the population level. Here, we used a novel saliva collection device designed to favour the safe and correct acquisition of the sample, as well as the processivity of the downstream molecular analysis. We tested 1003 nasopharyngeal swabs and paired saliva samples self-collected by individuals recruited at a public drive-through testing facility. An overall moderate concordance (68%) between the two tests was found, with evidence that neither system can diagnose the infection in 100% of the cases. While the two methods performed equally well in symptomatic individuals, their discordance was mainly restricted to samples from convalescent subjects. The saliva test was at least as effective as NP swabs in asymptomatic individuals recruited for contact tracing. Our study describes a testing strategy of self-collected saliva samples, which is reliable for wide-scale COVID-19 screening in the community and is particularly effective for contact tracing.

Nowadays, fused deposition modeling additive technology is becoming more and more popular in parts manufacturing due to its ability to reproduce complex geometries with many different thermoplastic materials, such as the TPU. On the other hand, objects obtained through this technology are mainly used for prototyping activities. For this reason, analyzing the functional behavior of FDM parts is still a topic of great interest. Many studies are conducted to broaden the spectrum of materials used to ensure an ever-increasing use of FDM in various production scenarios. In this study, the effects of several phenomena that influence the mechanical properties of printed lattice structures additively obtained by FDM are evaluated. Three different configurations of lattice structures with designs developed from unit cells were analyzed both experimentally and numerically. As the main result of the study, several parameters of the FDM process and their correlation were identified as possible detrimental factors of the mechanical properties by about 50% of the same parts used as isotropic cell solids. The best parameter configurations in terms of mechanical response were then highlighted by numerical analysis.

Background: Enterovirus infections can cause a variety of illnesses, ranging from asymptomatic infections to severe illness and death., Aim: To support polio eradication activities, in February 2019, the WHO Regional Reference Laboratory for polio in Italy, at the National Institute of Public Health (Istituto Superiore di Sanità), promoted an investigation on non-polio enterovirus laboratory capacity, with the support of the Italian Ministry of Health. The aim was to collect data on the assays used routinely for diagnostic purposes and to characterize enterovirus outbreaks strains by sequence analysis of the Viral Protein 1 region., Methods: A questionnaire was administered to public health laboratories through all Italian Regions for 2018 and subsequently, an electronic form for lab-confirmed enterovirus infection reported from February 2019 to January 2020, including patients clinical characteristics, and laboratory data was distributed through 25 laboratories participating the survey., Results: Overall, a homogenous laboratory capacity for enterovirus infection diagnosis was found and 21,000 diagnostic tests were retrospectively reported in 2018. Then, in 2019, two outbreaks of Echovirus 30 were identified and confirmed by molecular analyses., Conclusion: These results underline the need monitor the circulation of non-polio enterovirus to ascertain the real burden of the disease in the country., (Copyright © 2021 The Authors. Published by Elsevier B.V. All rights reserved.)

The study analysed the trend of toxoplasmosis infection in pregnancy by using antenatal serological screening and the incidence of the congenital condition in newborns in the province of Trento, Italy. Data from pregnant women who gave birth at local maternity units between 2009 and 2018 were obtained. The serological test results were collected from birth attendance certificates (BACs), the main - and mandatory - source of information used to monitor pregnancies, births and neonatal health in Italy. The BAC used in the province of Trento acquires the results of serological tests for a vast range of infections in pregnancy. The data collected from the BACs were integrated with those provided by the Hospital Information System (HIS), which was also used to collect data on the trimester in which the seroconversion occurred. A total of 45,492 pregnant women were analysed, of whom 24% were foreigners. The average coverage of serological screening in pregnancy was 99.7%. Mean overall prevalence of Toxoplasma gondii infection was 21.7% (95% CI: 21.3-22.1): in Italians the prevalence was 17.9% (95% CI: 17.5-18.30) and in foreign nationals 32.7% (95% CI: 32.26-33.13). The mean annual seroconversion rate was 0.35% (95% CI: 3.0-4.2) of susceptible women and 0.27% (95% CI: 2.2-3.4) of all pregnant women who were screened. The seroconversion rate was higher amongst foreign women (0.32%, 95% CI: 3.0-3.6) than Italian women (0.24%, 95% CI: 2.1-2.8). In all, 91.0% of seroconverted women were treated during pregnancy in accordance with the anti-toxoplasma protocol. Five cases of congenital infection were identified (2 amongst Italians and 3 amongst foreign women), amounting to an overall transmission rate of 4.0% (2.3% in Italians and 8.8% in foreigners). Transmission risk ranged from 0.0% in the first trimester to 19% in the third. The incidence of congenital toxoplasmosis, over the entire study period, was 0.012% live births (0.011% in Italians and 0.016% in foreigners). Data collection on infections in pregnancy through BAC allows area-based assessment. Although the quality of the data recorded in the BAC can be considered satisfactory, it was also necessary to access other information sources. The screening coverage was very high. The prevalence of toxoplasmosis infection was found to be higher in foreign mothers than in Italians, as well as seroconversion. The extent of serological screening and the high treatment rate helped to keep the risk of infection transmission to the foetus low and to achieve a very low rate of congenital infection.

Background: Rubella, syphilis, toxoplasmosis, cytomegalovirus (CMV), hepatitis B (HBV) and C (HCV), HIV, and Group B Streptococcus (GBS) infections may have very severe outcomes during pregnancy, and for this reason, monitoring of infections in pregnant women is a requirement of prenatal assistance., Aims: To describe coverage and outcome of the screening for rubella, syphilis, toxoplasmosis, CMV, HBV, HCV, HIV, and Group B Streptococcus in pregnancy in the Autonomous Province of Trento, Northern Italy (538,600 inhabitants)., Methods: We analysed the coverage and outcome of the above-mentioned screenings among women who delivered in the hospitals of the Province of Trento between 2007 and 2014 (N = 38,712). Screenings were grouped according to characteristics such as recommendation by national and local guidelines, scheduling of the tests, operating methods, and charge. We also estimated odds ratios (ORs) for missing screening for selected infections through multiple logistic regression., Results: Estimated uptake of antenatal screening was 99.7% for rubella, 99.3% for syphilis, 99.7% for toxoplasmosis, 98.1% for HIV infection, 99.0% for HBV, 98.9% for HCV, 94.0% for GBS infection, and 75.4% for CMV infection. The overall prevalence of immunity was 94.1% for rubella, 24.2% for toxoplasmosis, and 64.2% for CMV. The rate of seroconversion in pregnant women was 0.02% for rubella, 0.29% for toxoplasmosis, and 0.75% for CMV. The overall prevalence of infection was 0.94% for HBV, 0.53% for HCV, 22.3% for GBS, 0.29% for syphilis, and 0.13% for HIV. We found a significant positive association for all screening tests, between lack of testing and late first medical examination in pregnancy (ORs ranging from 1.20 to 1.66 for the first medical visit in the second trimester and ORs ranging from 1.60 to 5.88 for the first medical visit in third trimester, compared to early medical visit in the first trimester). Compared to Italian citizenship, foreign citizenship of the mother was also positively associated with absence of screening (ORs ranging from 1.30 to 1.53). A significant inverse association was observed for calendar year of delivery (ORs ranging from 0.71 to 0.97, for 1 year increment). Less educated mothers and pluriparae were also at higher risks of not being tested. Analysis of the association with mother age showed different heterogeneous effects., Conclusions: Our study indicates that the attention to screening and detecting infected cases is growing over the time. In addition, care delivered during pregnancy has a leading role in determining coverage of the examinations. Immigrant, pluriparous and less educated women need particular attention.

Shape-adaptive or morphing capability in both aerospace structures and wind turbineblade design is regarded as significant to increase aerodynamic performance and simplifymechanisms by reducing the number of moving parts. The underlying bistable behavior ofasymmetric cross-ply composites makes them a suitable candidate for morphing applications. Todate, various theoretical and experiential studies have been carried out to understand and predictthe bistable behavior of asymmetric laminates and especially the curvature obtained in their stableconfigurations. However, when the bi-stable composite plate is integrated with shape memory alloywires to control the curvature and to snap from a stable configuration to the other (shape memoryalloy composite, SMAC), the identification of the design parameters, namely laminate edge length,ply thickness and ply orientation, is not straightforward. The aim of this article is to present theformulation of an optimization problem for the parameters of an asymmetric composite laminateintegrated with pre-stressed shape memory alloys (SMA) wires under bi-stability and a minimumdeflection requirement. Wires are modeled as an additional ply placed at the mid-plane of thecomposite host plate. The optimization problem is solved numerically in MATLAB and optimaldesign variables are then used to model the SMAC in ABAQUS™. Finite element results arecompared against numerical results for validation.

In February 2017 a case of Hemolytic-Uremic Syndrome (HUS) was reported to the National Registry of HUS in an adult living in Northern Italy. Stool specimens from the patient and his family contacts were collected and the analyses led to the isolation of a Locus of Enterocyte Effacement (LEE)-negative Shiga toxin 2 (Stx2)-producing Escherichia coli. The epidemiological investigations performed brought to collect fecal samples from the animals reared in a farm held by the case's family and a mixture of bovine and swine feces proved positive for Shiga toxin-producing E. coli (STEC) and yielded the isolation of a LEE-negative stx2-positive E. coli strain. Further characterization by whole genome sequencing led to identify the isolates as two identical O2:H27 hybrid Enterotoxigenic Shiga toxin-producing E. coli (ETEC-STEC). Sequencing of a high molecular weight plasmid present in the human isolate disclosed a peculiar plasmid harboring virulence genes characteristic for both pathotypes, including the enterohemolysin-coding gene and sta1, encoding the heat stable enterotoxin. Moreover, a complete fae locus encoding the ETEC F4 fimbriae could be identified, including a novel variant of faeG gene responsible for the production of the main structural subunit of the fimbriae. This novel faeG showed great diversity in the nucleotidic sequence when compared with the reference genes encoding the swine F4 allelic variants, whereas at the amino acid sequence level the predicted protein sequence showed some similarity with FaeG from E. coli strains of bovine origin. Further investigation on the plasmid region harboring the newly identified faeG allelic variant allowed to identify similar plasmids in NCBI sequence database, as part of the genome of other previously uncharacterized ETEC-STEC strains of bovine origin, suggesting that the novel F4-like fimbriae may play a role in bovine host specificity., (Copyright © 2018 Elsevier GmbH. All rights reserved.)

A comparative electron microscopic analysis of weakly beta-haemolytic spirochaetes related to human and animal intestinal spirochaetosis was done in order to search for the presence of inducible bacteriophages associated with these spirochaetes. Bacteriophages were detected at the electron microscope after experimental induction with mitomycin C in 4 strains of weakly beta-haemolytic spirochaetes related to human intestinal spirochaetosis, in Serpulina pilosicoli strain P43/6/78, the causative agent of swine intestinal spirochaetosis, in a spirochaetal strain related to avian intestinal spirochaetosis, and in Serpulina hyodysenteriae, strain P18A, the causative agent of swine dysentery, which was comparatively analysed as control. All phage-particles observed in both human and animal intestinal spirochaetes were morphologically similar with an isometric head of 45 nm diameter and a tail 63-70 nm long and 7-12 nm width. The presence of morphologically similar phages in all the haemolytic intestinal spirochaetes of human and animal origin analysed in this study opens some important questions, about the genetic relationship of phages present in pathogenic intestinal spirochaetes, their host range, and the possibility of natural gene transfer among pathogenic haemolytic intestinal spirochaetes of human and animal origin.