337 research outputs found

    Use of Bio-Epoxies and Their Effect on the Performance of Polymer Composites: A Critical Review

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    This study comprehensively examines recent developments in bio-epoxy resins and their applications in composites. Despite the reliability of traditional epoxy systems, the increasing demand for sustainability has driven researchers and industries to explore new bio-based alternatives. Additionally, natural fibers have the potential to serve as environmentally friendly substitutes for synthetic ones, contributing to the production of lightweight and biodegradable composites. Enhancing the mechanical properties of these bio-composites also involves improving the compatibility between the matrix and fibers. The use of bio-epoxy resins facilitates better adhesion of natural composite constituents, addressing sustainability and environmental concerns. The principles and methods proposed for both available commercial and especially non-commercial bio-epoxy solutions are investigated, with a focus on promising renewable sources like wood, food waste, and vegetable oils. Bio-epoxy systems with a minimum bio-content of 20% are analyzed from a thermomechanical perspective. This review also discusses the effect of incorporating synthetic and natural fibers into bio-epoxy resins both on their own and in hybrid form. A comparative analysis is conducted against traditional epoxy-based references, with the aim of emphasizing viable alternatives. The focus is on addressing their benefits and challenges in applications fields such as aviation and the automotive industry

    LTE/Wi-Fi Co-existence under Scrutiny: An Empirical Study

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    Mobile operators are seeking to increase network capacity by extending Long Term Evolution (LTE) cellular operation into unlicensed frequency bands. While these efforts may respond to the projected exponential growth in mobile data traffic, significant concerns exist about the harmonious co-existence of LTE with incumbent Wi-Fi deployments. In this paper we characterise experimentally the LTE and Wi-Fi behaviour when sharing the same spectrum while operating under a broad range of network conditions. Specifically, we deploy a test bed with commodity Wi-Fi hardware and low-cost software-defined radio equipment running an open-source LTE stack. We investigate the user-level performance attainable over these technologies when employing different settings, including LTE duty cycling patterns, Wi-Fi offered loads, transmit power levels, modulation and coding schemes, and packet sizes. We show that co-existence is feasible without modifications to the Wi-Fi stack, if LTE periodically employs "silent" sub-frames; however, optimising the performance of both requires non-trivial tuning of multiple parameters in conjunction with close monitoring of Wi-Fi operation and detection of application-specific requirements. Our findings lay the foundations for coherent design of practical LTE/Wi-Fi co-existence mechanisms

    Cryptostroma corticale: malattia della corteccia fuligginosa dell'acero

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    Le segnalazioni di questa malattia che colpisce il genere Acer sono in crescita in tutta Europa. La sua recrudescenza pare legata al riscaldamento del clima. Oltre a portare a morte le piante e a comprometterne la stabilità meccanica, il fungo ascomicete che ne è causa, Cryptostoma corticale, minaccia la salute umana producendo una grande quantità di spore aeree che possono causare gravi infiammazioni polmonari

    Epidemiology and complications of late-onset sepsis: An Italian area-based study

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    Background Most studies regarding late-onset sepsis (LOS) address selected populations (i.e., neonates with low birth weight or extremely preterm neonates). Studying all age groups is more suitable to assess the burden of single pathogens and their clinical relevance. Methods This is a retrospective regional study involving paediatric departments and NICUs in Emilia-Romagna (Italy). Regional laboratory databases were searched from 2009 to 2012. Records of infants (aged 4 to 90 days) with a positive blood or cerebrospinal fluid (CSF) culture were retrospectively reviewed and analysed according to acquisition mode (whether hospital- or community-acquired). Results During the study period, there were 146,682 live births (LBs), with 296 patients experiencing 331 episodes of LOS (incidence rate: 2.3/1000 LBs). Brain lesions upon discharge from the hospital were found in 12.3% (40/296) of cases, with death occurring in 7.1% (23/296; 0.14/ 1000 LBs). With respect to full-term neonates, extremely preterm or extremely low birth weight neonates had very high risk of LOS and related mortality (> 100- and > 800-fold higher respectively). Hospital-acquired LOS (n = 209) was significantly associated with very low birth weight, extremely preterm birth, pneumonia, mechanical ventilation, and death (p< 0.01). At multivariate logistic regression analysis, catecholamine support (OR = 3.2), central venous line before LOS (OR = 14.9), and meningitis (OR = 44.7) were associated with brain lesions or death in hospital-acquired LOS (area under the ROC curve 0.81, H-L p = 0.41). Commonly identified pathogens included coagulase-negative staphylococci (CoNS n = 71, 21.4%), Escherichia coli (n = 50, 15.1%), Staphylococcus aureus (n = 41, 12.4%) and Enterobacteriaceae (n = 41, 12.4%). Group B streptococcus was the predominant cause of meningitis (16 of 38 cases, 42%). Most pathogens were sensitive to first line antibiotics. Conclusions This study provides the first Italian data regarding late-onset sepsis (LOS) in all gestational age groups. Compared to full-term neonates, very high rates of LOS and mortality occurred in neonates with a lower birth weight and gestational age. Group B streptococcus was the leading cause of meningitis. Excluding CoNS, the predominant pathogens were Escherichia coli and Staphylococcus aureus. Neonates with hospital-acquired LOS had a worse outcome. Antibiotic associations, recommended for empirical treatment of hospital- or community-acquired LOS, were adequate

    Body composition parameters, immunonutritional indexes, and surgical outcome of pancreatic cancer patients resected after neoadjuvant therapy: A retrospective, multicenter analysis

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    Background and aims: Body composition parameters and immunonutritional indexes provide useful information on the nutritional and inflammatory status of patients. We sought to investigate whether they predict the postoperative outcome in patients with pancreatic cancer (PC) who received neoadjuvant therapy (NAT) and then pancreaticoduodenectomy. Methods: Data from locally advanced PC patients who underwent NAT followed by pancreaticoduodenectomy between January 2012 and December 2019 in four high-volume institutions were collected retrospectively. Only patients with two available CT scans (before and after NAT) and immunonutritional indexes (before surgery) available were included. Body composition was assessed and immunonutritional indexes collected were: VAT, SAT, SMI, SMA, PLR, NLR, LMR, and PNI. The postoperative outcomes evaluated were overall morbidity (any complication occurring), major complications (Clavien-Dindo ≥ 3), and length of stay. Results: One hundred twenty-one patients met the inclusion criteria and constituted the study population. The median age at the diagnosis was 64 years (IQR16), and the median BMI was 24 kg/m2 (IQR 4.1). The median time between the two CT-scan examined was 188 days (IQR 48). Skeletal muscle index (SMI) decreased after NAT, with a median delta of −7.8 cm2/m2 (p < 0.05). Major complications occurred more frequently in patients with a lower pre-NAT SMI (p = 0.035) and in those who gained in subcutaneous adipose tissue (SAT) compartment during NAT (p = 0.043). Patients with a gain in SMI experienced fewer major postoperative complications (p = 0.002). The presence of Low muscle mass after NAT was associated with a longer hospital stay [Beta 5.1, 95%CI (1.5, 8.7), p = 0.006]. An increase in SMI from 35 to 40 cm2/m2 was a protective factor with respect to overall postoperative complications [OR 0.43, 95% (CI 0.21, 0.86), p < 0.001]. None of the immunonutritional indexes investigated predicted the postoperative outcome. Conclusion: Body composition changes during NAT are associated with surgical outcome in PC patients who receive pancreaticoduodenectomy after NAT. An increase in SMI during NAT should be favored to ameliorate the postoperative outcome. Immunonutritional indexes did not show to be capable of predicting the surgical outcome

    Timing of Symptoms of Early-Onset Sepsis after Intrapartum Antibiotic Prophylaxis: Can It Inform the Neonatal Management?

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    The effectiveness of “inadequate” intrapartum antibiotic prophylaxis (IAP administered < 4 h prior to delivery) in preventing early-onset sepsis (EOS) is debated. Italian prospective surveillance cohort data (2003–2022) were used to study the type and duration of IAP according to the timing of symptoms onset of group B streptococcus (GBS) and E. coli culture-confirmed EOS cases. IAP was defined “active” when the pathogen yielded in cultures was susceptible. We identified 263 EOS cases (GBS = 191; E. coli = 72). Among GBS EOS, 25% had received IAP (always active when beta-lactams were administered). Most IAP-exposed neonates with GBS were symptomatic at birth (67%) or remained asymptomatic (25%), regardless of IAP duration. Among E. coli EOS, 60% were IAP-exposed. However, IAP was active in only 8% of cases, and these newborns remained asymptomatic or presented with symptoms prior to 6 h of life. In contrast, most newborns exposed to an “inactive” IAP (52%) developed symptoms from 1 to >48 h of life. The key element to define IAP “adequate” seems the pathogen’s antimicrobial susceptibility rather than its duration. Newborns exposed to an active antimicrobial (as frequently occurs with GBS infections), who remain asymptomatic in the first 6 h of life, are likely uninfected. Because E. coli isolates are often unsusceptible to beta-lactam antibiotics, IAP-exposed neonates frequently develop symptoms of EOS after birth, up to 48 h of life and beyond

    The increasing threat to European forests from the invasive foliar pine pathogen, Lecanosticta acicola

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    European forests are threatened by increasing numbers of invasive pests and pathogens. Over the past century, Lecanosticta acicola, a foliar pathogen predominantly of Pinus spp., has expanded its range globally, and is increasing in impact. Lecanosticta acicola causes brown spot needle blight, resulting in premature defoliation, reduced growth, and mortality in some hosts. Originating from southern regions of North American, it devastated forests in the USA's southern states in the early twentieth century, and in 1942 was discovered in Spain.Derived from Euphresco project 'Brownspotrisk,' this study aimed to establish the current distribution of Lecanosticta species, and assess the risks of L. acicola to European forests. Pathogen reports from the literature, and new/ unpublished survey data were combined into an open-access geo-database (http://www.portaloff orestpathology.com), and used to visualise the pathogen's range, infer its climatic tolerance, and update its host range. Lecanosticta species have now been recorded in 44 countries, mostly in the northern hemisphere. The type species, L. acicola, has increased its range in recent years, and is present in 24 out of the 26 European countries where data were available. Other species of Lecanosticta are largely restricted to Mexico and Central America, and recently Colombia.The geo-database records demonstrate that L. acicola tolerates a wide range of climates across the northern hemisphere, and indicate its potential to colonise Pinus spp. forests across large swathes of the Europe. Pre-liminary analyses suggest L. acicola could affect 62% of global Pinus species area by the end of this century, under climate change predictions.Although its host range appears slightly narrower than the similar Dothistroma species, Lecanosticta species were recorded on 70 host taxa, mostly Pinus spp., but including, Cedrus and Picea spp. Twenty-three, including species of critical ecological, environmental and economic significance in Europe, are highly susceptible to L. acicola, suffering heavy defoliation and sometimes mortality. Variation in apparent susceptibility between reports could reflect variation between regions in the hosts' genetic make-up, but could also reflect the signif-icant variation in L. acicola populations and lineages found across Europe. This study served to highlight sig-nificant gaps in our understanding of the pathogen's behaviour.Lecanosticta acicola has recently been downgraded from an A1 quarantine pest to a regulated non quarantine pathogen, and is now widely distributed across Europe. With a need to consider disease management, this study also explored global BSNB strategies, and used Case Studies to summarise the tactics employed to date in Europe

    The Italian arm of the PREPARE study: an international project to evaluate and license a maternal vaccine against group B streptococcus.

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    BACKGROUND: Group B streptococcus (GBS) is a leading cause of sepsis, pneumonia and meningitis in infants, with long term neurodevelopmental sequelae. GBS may be associated with poor pregnancy outcomes, including spontaneous abortion, stillbirth and preterm birth. Intrapartum antibiotic prophylaxis (IAP) is currently the only way to prevent early-onset disease (presenting at 0 to 6 days of life), although it has no impact on the disease presenting over 6 days of life and its implementation is challenging in resource poor countries. A maternal vaccine against GBS could reduce all GBS manifestations as well as improve pregnancy outcomes, even in low-income countries. MAIN BODY: The term "PREPARE" designates an international project aimed at developing a maternal vaccination platform to test vaccines against neonatal GBS infections by maternal immunization. It is a non-profit, multi-center, interventional and experimental study (promoted by the St George University of London. [UK]) with the aim of developing a maternal vaccination platform, determining pregnancy outcomes, and defining the extent of GBS infections in children and mothers in Africa. PREPARE also aims to estimate the protective serocorrelates against the main GBS serotypes that cause diseases in Europe and Africa and to conduct two trials on candidate GBS vaccines. PREPARE consists of 6 work packages. In four European countries (Italy, UK, Netherlands, France) the recruitment of cases and controls will start in 2020 and will end in 2022. The Italian PREPARE network includes 41 centers. The Italian network aims to collect: GBS isolates from infants with invasive disease, maternal and neonatal sera (cases); cord sera and GBS strains from colonized mothers whose infants do not develop GBS infection (controls). SHORT CONCLUSION: PREPARE will contribute information on protective serocorrelates against the main GBS serotypes that cause diseases in Europe and Africa. The vaccine that will be tested by the PREPARE study could be an effective strategy to prevent GBS disease
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