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The recycling of polyvinylchloride (PVC) from waste electrical cables in blends with low-density polyethylene (LDPE) is here explored, focusing on the material's mechanical and physical responses. Factors influencing these responses were identified, and reasonable ranges of variability were estimated for each factor. A comprehensive test plan was subsequently devised to develop optimal PVC/LDPE blends. The samples were produced by melt-blending the polymers in a counter-rotating internal mixer followed by compression molding. The effects of suitable coupling additives were also evaluated to enhance phases adhesion. The study investigated the impact of various processing parameters on thermomechanical properties using ANOVA, while a specific focus on optimizing material toughness was pursued. This optimization aimed to maximize both elastic modulus and elongation at break, through the application of genetic algorithms. Introducing a 5 % compatibilizer significantly enhances the interface, resulting in a complex fracture surface facilitated by its presence. Higher mixing temperatures promote better dispersion and distribution of PVC and the compatibilizer within the LDPE matrix, yielding a more uniform and interconnected structure. Increased PVC content correlates with reduced elastic modulus in the blend. The inclusion of a compatibilizer plays a vital role in counteracting the negative effects of PVC particles on stiffness, acting as a bridge to enhance interactions with the matrix and thereby improving interfacial adhesion and overall structure. The study offers insights into enhancing the recyclability of PVC from waste cables and optimizing the mechanical performance of the resultant materials.

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This study was focused on the development of novel bio-based and biodegradable hydrogels constituted of xanthan gum (XG) reinforced with wood fibers, to be used as eco-sustainable topsoil covers (TSCs) in support of reforestation and agricultural efforts in arid conditions. At this aim, hydrogels were developed by cross-linking XG with citric acid (CA), sodium trimetaphosphate (STMP) or tannic acid (TA) at different concentrations. Samples cross-linked with CA and TA exhibited the highest dimensional stability and exceptional water absorption capability, even after multiple absorption/drying cycles. Hydrogels with 50, 60, and 100 phr of CA displayed water vapor permeance values of about 9.5·10−6 g/(Pa·s·m2), i.e., comparable to commercial woven PP mulching films. The average penetration resistance of the produced hydrogels was twice that of the commercial one. The presence of wood fibers in the hydrogels provided dimensional stability and minimal shrinkage after exposure to outdoor conditions for two months (15.4 % for sample with 60 phr of CA). Furthermore, after 7 months of exposure, more than 60 % of the sample mass was biodegraded. This research demonstrated the potential of xanthan gum/wood fibers based hydrogels as TSCs with superior water-regulating properties, thus offering a simple, cost-effective and scalable technology for forestry and agriculture applications.

Implementing retrofitting measures for a civil structure may guarantee its ongoing safety and operation, while also extending its lifespan. The present investigation focused on the examination of compressive axial loads on concrete columns that were confined by natural fiber reinforced polymer (FRP). In particular, concrete cylinders confined with jute and basalt fiber epoxy composites were evaluated for their strength and durability. Various strength tests were conducted on unconfined and, jute, basalt, and hybrid jute-basalt FRP confined concrete cylinders with varying thicknesses of the FRP layers. Effectiveness of these natural FRP systems in providing external confinement to concrete columns in various environmental conditions were investigated, including exposure to acidic, alkaline, seawater, and potable water environments. Test results demonstrated that external confinement with hybrid FRP wraps, i.e. with both jute and basalt fibers, enhanced the load-bearing and energy absorption capacities by 63.64 % and 287 %, respectively. The confinement effectiveness of FRP wrapped specimens were 213 %, 164 %, 166 % and 163 % respectively compared to the unconfined specimens after exposure to acidic, alkaline, seawater and potable water environments. These impressive outcomes may be ascribed to the intrinsic rigidity of hybrid fibers. Furthermore, a finite element analysis (FEA) model of FRP confined concrete columns was performed using ABAQUS software calibrated with the experimental data. A close agreement between the experimental results and the adopted numerical model was observed. The outcome of the study suggests that the confinement with natural FRP can be used as a prominent retrofitting technique for columns in a variety of environments which can thus enhance the durability and sustainability of civil constructions.

The essay focuses on Dante’s divisio scientiae presented in the second book of his Convivio. As a first step, it offers a fresh reading of Dante’s description of knowledge and the cosmos, emphasizing its deeply visual nature. The article then presents an overview of the Medieval tradition of the divisio scientiae, culminating with divisions that are geographically and chronologically close to Dante’s Florence. In relation to Brunetto Latini’s Rettorica and Tresor, new evidence is provided to elucidate his peculiar division of logic. Ultimately, Dante’s divisio and its objectives are reassessed in light of their historical background, underscoring their cosmological and totalizing scope. Adopting an interdisciplinary approach, the findings consider cognitive practices, such as diagrams, and examine a wide array of sources within their historical and institutional context, highlighting their transmission and dissemination.

This study investigated the self-healing properties of PA6/COC blends, in particular, the impact of three compatibilizers on the rheological, microstructural, and thermomechanical properties. Dynamic rheological analysis revealed that ethylene glycidyl methacrylate (E-GMA) played a crucial role in reducing interfacial tension and promoting PA6 chain entanglement with COC domains. Mechanical tests showed that poly(ethylene)-graft-maleic anhydride (PE-g-MAH) and polyolefin elastomer-graft-maleic anhydride (POE-g-MAH) compatibilizers enhanced elongation at break, while E-GMA had a milder effect. A thermal healing process at 140 °C for 1 h was carried out on specimens broken in fracture toughness tests, performed under quasi-static and impact conditions, and healing efficiency (HE) was evaluated as the ratio of critical stress intensity factors of healed and virgin samples. All the compatibilizers increased HE, especially E-GMA, achieving 28.5% and 68% in quasi-static and impact conditions, respectively. SEM images of specimens tested in quasi-static conditions showed that all the compatibilizers induced PA6 plasticization and crack corrugation, thus hindering COC flow in the crack zone. Conversely, under impact conditions, E-GMA led to the formation of brittle fractures with planar surfaces, promoting COC flow and thus higher HE values. This study demonstrated that compatibilizers, loading mode, and fracture surface morphologies strongly influenced self-healing performance.

In the contemporary emphasis on weight reduction, the utilization of advanced materials like Carbon Fiber Reinforced Polymers (CFRPs) and cutting-edge technologies such as 3D printing of metal is increasingly crucial. This study delves into the junction of CFRP and titanium, aiming to conduct Single Lap shear tests on specimens featuring a co-lamination of long fiber composite onto a metal lattice structure. Different specimens with different dimensions of the Simple Cubic (SC) unit cell were subjected to testing. A microscope investigation facilitated an exploration of junction failure and epoxy resin infiltration into the lattice substrate. Employing an efficient 2D Finite Element Model, the homogenization process yielded theoretical models underestimating the Young Modulus by approximately 10% compared to real specimens. Despite the challenges in bonding titanium and CFRP, the novel junction exhibited a shear stress of 17.25 MPa, which is nearly equivalent to those of a co-lamination between sandblasted steel and CFRP, that is 17.15 MPa.

This document is a collection of abstracts from the Journal of Neonatal - Perinatal Medicine. The abstracts cover various topics related to neonatal neurodevelopment and brain abnormalities in preterm infants. One study focuses on the use of MRI in predicting long-term outcomes in infants with Hypoxic Ischemic Encephalopathy. Another study explores the prediction of post-hemorrhagic ventricular dilatation in preterm infants with intraventricular hemorrhage. A third study examines the impact of cerebellar hemorrhage on the neurodevelopmental outcomes of extremely preterm infants. The fourth abstract compares the utility of early and late MRI in evaluating infants with Neonatal Encephalopathy. Additionally, there is a study investigating the impact of SARS-CoV-2 infection during pregnancy on neonatal neurological outcomes. Lastly, a study explores the hemodynamic responses associated with spontaneous neural activity in the early developing brain. These abstracts provide valuable insights into neonatal neurodevelopment and brain abnormalities in preterm infants. [Extracted from the article]

In fiber reinforced composite materials, the interfacial strength between the fibers and the matrix plays a key role in controlling the stress transfer and damage mechanisms of the composite. In this study, CO2 laser surface treatment of the fibers was investigated as a potential sustainable substitute for conventional chemical treatments, that can be costly and have negative environmental effects. The influence of the laser treatment on basalt fiber fabric was comprehensively investigated. The fibers were subjected to different laser power levels and characterized from a morphological and mechanical point of view. From optical and scanning electron microscopy, it was observed that the treated fibers manifested increased surface roughness along with spots of fused and bonded fibers. Individual treated fibers exhibited improved tensile properties with increased values of scale parameter (by about 21%) in the case of a laser power equal to 1.04 W/mm2, and no substantial changes in Young's modulus. The treated fibers were subsequently used in the preparation of epoxy‐based microcomposites, and microdebonding tests revealed an increase in the interfacial shear strength (IFSS) up to 8%. Therefore, this work proved that a laser surface treatment of basalt fibers is a valid alternative to conventional fiber surface modification to enhance the mechanical compatibility between fibers and matrix, and therefore to improve the mechanical performances of basalt fiber composites. Highlights: Failure in composites due to weak interfacial adhesion with epoxy.CO2 laser treatment of basalt fibers to enhance interfacial adhesion.Treated fibers exhibit improved tensile properties.Treated fibers manifested improved interfacial shear strength (IFSS, +8%). [ABSTRACT FROM AUTHOR]

The essay focuses on Dante's divisio scientiae presented in the second book of his Convivio. As a first step, it offers a fresh reading of Dante's description of knowledge and the cosmos, emphasizing its deeply visual nature. The article then presents an overview of the Medieval tradition of the divisio scientiae, culminating with divisions that are geographically and chronologically close to Dante's Florence. In relation to Brunetto Latini's Rettorica and Tresor, new evidence is provided to elucidate his peculiar division of logic. Ultimately, Dante's divisio and its objectives are reassessed in light of their historical background, underscoring their cosmological and totalizing scope. Adopting an interdisciplinary approach, the findings consider cognitive practices, such as diagrams, and examine a wide array of sources within their historical and institutional context, highlighting their transmission and dissemination. [ABSTRACT FROM AUTHOR]

This study investigated the self-healing properties of PA6/COC blends, in particular, the impact of three compatibilizers on the rheological, microstructural, and thermomechanical properties. Dynamic rheological analysis revealed that ethylene glycidyl methacrylate (E-GMA) played a crucial role in reducing interfacial tension and promoting PA6 chain entanglement with COC domains. Mechanical tests showed that poly(ethylene)-graft-maleic anhydride (PE-g-MAH) and polyolefin elastomer-graft-maleic anhydride (POE-g-MAH) compatibilizers enhanced elongation at break, while E-GMA had a milder effect. A thermal healing process at 140 °C for 1 h was carried out on specimens broken in fracture toughness tests, performed under quasi-static and impact conditions, and healing efficiency (HE) was evaluated as the ratio of critical stress intensity factors of healed and virgin samples. All the compatibilizers increased HE, especially E-GMA, achieving 28.5% and 68% in quasi-static and impact conditions, respectively. SEM images of specimens tested in quasi-static conditions showed that all the compatibilizers induced PA6 plasticization and crack corrugation, thus hindering COC flow in the crack zone. Conversely, under impact conditions, E-GMA led to the formation of brittle fractures with planar surfaces, promoting COC flow and thus higher HE values. This study demonstrated that compatibilizers, loading mode, and fracture surface morphologies strongly influenced self-healing performance. [ABSTRACT FROM AUTHOR]

In the contemporary emphasis on weight reduction, the utilization of advanced materials like Carbon Fiber Reinforced Polymers (CFRPs) and cutting-edge technologies such as 3D printing of metal is increasingly crucial. This study delves into the junction of CFRP and titanium, aiming to conduct Single Lap shear tests on specimens featuring a co-lamination of long fiber composite onto a metal lattice structure. Different specimens with different dimensions of the Simple Cubic (SC) unit cell were subjected to testing. A microscope investigation facilitated an exploration of junction failure and epoxy resin infiltration into the lattice substrate. Employing an efficient 2D Finite Element Model, the homogenization process yielded theoretical models underestimating the Young Modulus by approximately 10% compared to real specimens. Despite the challenges in bonding titanium and CFRP, the novel junction exhibited a shear stress of 17.25 MPa, which is nearly equivalent to those of a co-lamination between sandblasted steel and CFRP, that is 17.15 MPa. [ABSTRACT FROM AUTHOR]

In this work, for the first time, carbon fibers (CFs) were coated with nanosized‐polycaprolactone (PCL) particles to obtain a functionalized self‐healable interphase, capable to fully recover the pristine interfacial shear strength with a debonded epoxy matrix. PCL nanoparticles were initially water‐dispersed at different concentrations and deposited on CFs by electrophoretic deposition. The application of various voltage levels resulted in different morphologies of the coating. Epoxy microdroplets were deposited and cured on neat and PCL‐coated fibers. After complete interfacial debonding by microdebonding tests, an electric current was applied on CFs to activate a thermal interfacial healing by Joule effect. The healing efficiency was estimated as the ratio of interfacial shear strength measured before and after healing. An outstanding repairing efficiency was obtained upon thermal mending with a complete recovery of the original interfacial shear strength, thus indicating a strong potential of the PCL nanocoating as interfacial healing agent for composite structures. Highlights: CFs were coated with nanosized‐PCL particles to obtain a functionalized self‐healable interphase.Electrophoretic deposition was employed for the fiber coating.Microdebonding tests were performed to assess the fiber/matrix interfacial properties in terms of interfacial shear strength.A full recovery of the interfacial properties was obtained via thermal interfacial healing by Joule effect. [ABSTRACT FROM AUTHOR]

Introduction: Fetal surgery for open spina bifida (OSB) requires comprehensive preoperative assessment using imaging for appropriate patient selection and to evaluate postoperative efficacy and complications. We explored patient access and conduct of fetal magnetic resonance imaging (MRI) for prenatal assessment of OSB patients eligible for fetal surgery. We compared imaging acquisition and reporting to the International Society of Ultrasound in Obstetrics and Gynecology MRI performance guidelines. Material and methods: We surveyed access to fetal MRI for OSB in referring fetal medicine units (FMUs) in the UK and Ireland, and two NHS England specialist commissioned fetal surgery centers (FSCs) at University College London Hospital, and University Hospitals KU Leuven Belgium. To study MRI acquisition protocols, we retrospectively analyzed fetal MRI images before and after fetal surgery for OSB. Results: MRI for fetal OSB was accessible with appropriate specialists available to supervise, perform, and report scans. The average time to arrange a fetal MRI appointment from request was 4 ± 3 days (range, 0–10), the average scan time available was 37 ± 16 min (range, 20–80 min), with 15 ± 11 min (range, 0–30 min) extra time to repeat sequences as required. Specific MRI acquisition protocols, and MRI reporting templates were available in only 32% and 18% of units, respectively. Satisfactory T2‐weighted (T2W) brain imaging acquired in three orthogonal planes was achieved preoperatively in all centers, and 6 weeks postoperatively in 96% of FSCs and 78% of referring FMUs. However, for T2W spine image acquisition referring FMUs were less able to provide three orthogonal planes presurgery (98% FSC vs. 50% FMU, p < 0.001), and 6 weeks post‐surgery (100% FSC vs. 48% FMU, p < 0.001). Other standard imaging recommendations such as T1‐weighted (T1W), gradient echo (GE) or echoplanar fetal brain and spine imaging in one or two orthogonal planes were more likely available in FSCs compared to FMUs pre‐ and post‐surgery (p < 0.001). Conclusions: There was timely access to supervised MRI for OSB fetal surgery assessment. However, the provision of images of the fetal brain and spine in sufficient orthogonal planes, which are required for determining eligibility and to determine the reversal of hindbrain herniation after fetal surgery, were less frequently acquired. Our evidence suggests the need for specific guidance in relation to fetal MRI for OSB. We propose an example guidance for MRI acquisition and reporting. [ABSTRACT FROM AUTHOR]

The article explores the rise of interdisciplinarity in research, emphasizing its effectiveness in addressing complex scientific and societal issues through collaborative efforts. Topics discussed include the integration of diverse disciplines in polymer research, the growing recognition of interdisciplinary approaches in funding and university rankings, and specific examples where interdisciplinary cooperation has led to successful innovations in various fields.