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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.

Ethylene Propylene Diene Monomer (EPDM) rubber foams are widely employed for thermal and acoustic insulation in building construction. However, their installation in confined spaces is often complicated, and the capability of EPDM foams to exhibit shape memory behavior could be a desirable property. In the literature, several works have demonstrated that blending elastomeric matrices with paraffin, a well-known Phase Change Material (PCM), could be an interesting method to obtain shape memory polymers with a tunable switching temperature. In this work, EPDM foams filled with paraffin wax, having a melting temperature of 70[degrees] C, were produced and characterized from a microstructural and thermo-mechanical point of view. By melt compounding and hot pressing, samples were produced, and the PCM content in the foams was varied between 0 and 60 wt% (with respect to the EPDM matrix). The results of the shape memory tests evidenced the crucial role played by the PCM in providing excellent shape fixability for the expanded rubber. Even a limited amount of paraffin (i.e., 20 wt%) was able to raise the strain fixity parameter to a value higher than 80%, and it reached 100% when the paraffin content was increased to 60 wt %. On the other hand, an increased PCM fraction caused a slower recovery process. Consequently, a compromise between a fast recovery and optimum shape fixability should be accepted. These results are promising for the development of novel thermal and acoustic EPDM insulating foams easier to be installed. KEYWORDS EPDM, paraffin, polymer foams, rubber, shape memory polymers, 1 | INTRODUCTION Shape memory polymers (SMPs) are smart materials that have drawn much interest due to their practical functions and potential uses in a multitude of sectors, including aeronautical [...]

Abstract Poly(vinylidene fluoride)/thermoplastic polyurethane (PVDF/TPU) composites filled with carbon‐black polypyrrole were prepared via melt compounding followed by compression molding and fused filament fabrication. CB‐PPy was added to the blends from 0 up to 15% to possible act as nucleating filler for PVDF β phase in order to increase its piezoelectric response. The influence of blending PVDF and TPU and of the addition of CB‐PPy on the overall crystallinity, content of β phase, and piezoelectric response of composites were investigated by differential scanning calorimetry (DSC), Fourier‐transformed infrared spectroscopy (FTIR), X‐ray diffraction (XRD) and determination of the piezoelectric coefficient (d33). It was found that the addition of TPU to PVDF induced an increase of the crystallinity degree and content of β phase in PVDF. Moreover, although the degree of crystallinity of the composites decreased with the addition of CB‐PPy, the percentage of β phase in PVDF was increased. This effect is more significant in samples with filler concentration higher than 6 wt%. As expected, the d33 of the composites increased as the content of the β phase increased. Furthermore, 3D printed samples displayed lower content of β phase and reduced piezoelectric responses when compared to compression molded samples with same composition.

The purpose of this work is to propose a decision-making algorithm to select the optimal composite material for thermally conductive but electrically insulating applications, such as microelectronic packaging heat sinks, diodes, and other electronic devices. In particular, an algorithm based on the criteria importance through inter-criteria correlation (CRITIC) and additive ratio assessment (ARAS) methods are used to evaluate several conflicting attributes. The evaluated samples were acrylonitrile butadiene styrene (ABS) composites filled with 0–30 vol% of boron nitride (BN) particles and prepared through melt compounding. The performance attributes considered through testing were heat conductivity, electrical resistivity, density, hardness, and tensile properties (Young's modulus, tensile strength, and elongation). As expected, the composite containing 30 vol% BN exhibited the highest heat conductivity, electrical resistivity, and Young's modulus. Meanwhile, unfilled ABS had the highest elongation at break, tensile strength, and lowest density. With respect to hardness, the 1 vol% BN-loaded composite proved to be superior. Therefore, the experimental data revealed a considerable compositional dependence with no obvious trend. The optimal composition was identified by adopting the CRITIC-ARAS multi-criteria decision-making algorithm, based on which the 30 vol% BN-containing composite was dominant among all the prepared samples. A validation through other decision-making techniques was performed to support the robustness of the proposed technique. Additionally, a sensitivity analysis was carried out on several weight exchange scenarios to see the stability of the ranking results.

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 Isolated remethylation defects are rare inherited diseases caused by a defective remethylation of homocysteine to methionine, preventing various essential methylation reactions to occur. Patients present with a systemic phenotype, which can especially affect the central and peripheral nervous systems leading to epileptic encephalopathy, developmental delay and peripheral neuropathy. Respiratory failure has been described in some cases, caused by both central and peripheral neurological involvement. In published cases, the genetic diagnosis and initiation of appropriate therapy were rapidly performed following respiratory failure and led to a rapid recovery of respiratory insufficiency within days. Here, we present two infantile‐onset cases of isolated remethylation defects, cobalamine (Cbl)G and methylenetetrahydrofolate reductase (MTHFR) deficiencies, which were diagnosed after several months of respiratory failure. Disease modifying therapy based on hydroxocobalamin and betaine was initiated and shows a progressive improvement and enabled weaning off respiratory support after 21 and 17 months in CblG and MTHFR patients respectively. We show that prolonged respiratory failure responds to conventional therapy in isolated remethylation defects, but can require a sustained period of time before observing a full response to therapy.

Abstract TNF signaling is an essential regulator of cellular homeostasis. Through its two receptors TNFR1 and TNFR2, soluble versus membrane-bound TNF enable cell death or survival in a variety of cell types. TNF-TNFRs signaling orchestrates important biological functions such as inflammation, neuronal activity as well as tissue de- and regeneration. TNF-TNFRs signaling is a therapeutic target for neurodegenerative diseases such as multiple sclerosis (MS) and Alzheimer’s disease (AD), but animal and clinical studies yielded conflicting findings. Here, we ask whether a sequential modulation of TNFR1 and TNFR2 signaling is beneficial in experimental autoimmune encephalomyelitis (EAE), an experimental mouse model that recapitulates inflammatory and demyelinating aspects of MS. To this end, human TNFR1 antagonist and TNFR2 agonist were administered peripherally at different stages of disease development in TNFR-humanized mice. We found that stimulating TNFR2 before onset of symptoms leads to improved response to anti-TNFR1 therapeutic treatment. This sequential treatment was more effective in decreasing paralysis symptoms and demyelination, when compared to single treatments. Interestingly, the frequency of the different immune cell subsets is unaffected by TNFR modulation. Nevertheless, treatment with only a TNFR1 antagonist increases T-cell infiltration in the central nervous system (CNS) and B-cell cuffing at the perivascular sites, whereas a TNFR2 agonist promotes Treg CNS accumulation. Our findings highlight the complicated nature of TNF signaling which requires a timely balance of selective activation and inhibition of TNFRs in order to exert therapeutic effects in the context of CNS autoimmunity.

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.

The increasing motorisation rate worldwide is responsible for the demand of huge quantities of tyres that, after their useful service life, become waste and should be properly managed. Due to the relative low cost of tyres and the complexity related to recycling, worldwide around 41% of the total amount of end-of-life tyres is discarded into landfills or stockpiles without any recovery of the material or of the energy. Moreover, the chemical composition of tyres makes them extremely resistant to degradation phenomena with a potential long-term permanence in the environment. The high energy amount required for the production of tyres and the related environmental impact should encourage the recycling of tyres and also promote the adoption of maintenance activities, such as retreading, that allow a considerable increase in the useful service life of tyres with consequent reduction in GHG emissions. In this article the relevant literature describing the current status of end-of-life options worldwide, the European legislation regarding tyre waste, their possible uses and the related environmental aspects are presented.

Materials able to store thermal energy can be a useful strategy to reduce energy consumption of buildings and to decrease greenhouse gases emissions. In this work, for the first time, the technique of salt leaching has been used to produce novel polyethylene foams containing different amounts of a microencapsulated phase-change material (PCM) with a melting point of 24[degrees]C, to be potentially applied in building insulation. The microstructural, thermal, and mechanical properties of produced foams have been comprehensively investigated. The prepared foams were characterized by high values of open porosity (about 60%) and by density values around 0.4 g/[cm.sup.3]. Infrared thermography analysis demonstrated that the time required from the samples to reach a set temperature, thanks to the presence of PCM, was up to two times higher with respect to the reference foam. Therefore, these materials could store/release an interesting amount of thermal energy. Shore-A measurements evidenced that the addition of PCM generally led to a softening of the foams. Tensile mechanical tests confirmed the softening effect provided by the addition of the microcapsules, with a decrease of the stiffness and of the strength of the material. Interestingly, strain-at-break values were considerably increased upon PCM introduction. KEYWORDS foams, phase-change materials, polyethylene, salt leaching, thermal energy storage, 1 | INTRODUCTION Recently, the improved living conditions of people and the increase of growth rate of population have led to an enhancement of the energy demands for buildings. Recent [...]

The aim of this study was to investigate the effect of different types of natural cellulose-based fillers on the properties of Xanthan gum (XG) in order to develop novel bio-based soil conditioners (SCs) that could be used in forestry and agricultural applications. Rheological measurements highlighted that SCs with cellulose fillers characterized by a high aspect ratio and low oxide ash content exhibited an average increase of 21% in yield stress compared to neat Xanthan gum. The presence of cellulose fillers in the composites resulted in a slower water release than that of neat XG, limiting the volumetric shrinkage during the drying process. Furthermore, an analysis of the water absorption and water retention capacity of soils treated with the different SCs was carried out, demonstrating that the addition of 1.8 wt.% of SC with optimized composition to the soil led to an increase in water absorption capacity from 34% up to 69%. From the soil water retention curves, it was observed that the addition of SCs significantly increased the amount of water effectively available for plants in the area between field capacity and permanent wilting point (100–1000 kPa). From practical experiments on grass growth, it was observed that these SCs improved the water regulation of the soil, thus increasing the probability of plant survival under drought conditions.

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]

High-density polyethylene (HDPE) is a highly versatile plastic utilized in various applicative fields such as packaging, agriculture, construction, and consumer goods. Unfortunately, the extensive use of polyethylene has resulted in a substantial accumulation of plastic waste, creating environmental and economic challenges. Consequently, the recycling of polyethylene has become a critical concern in recent times. This work focuses on the recycling of HDPE parts recovered from end-of-life boats into materials suitable for the marine environment with additive manufacturing technology via screw-assisted extrusion 3D printing. In particular, rigid materials are obtained by adding glass fibers to HDPE to mitigate the loss of mechanical performance upon recycling. Eventually, the properties obtained with two different production methods were compared, namely compression molding and screw-assisted extrusion 3D printing. Since the developed materials will be exposed to an aggressive environment, an extended thermos-mechanical characterization (including fatigue resistance) and investigation of the stability to UV exposure were performed.

Este artigo visa refletir sobre possibilidades da forma urbana para o século XXI, como contribuição aosestudos sobre áreas centrais, tendo como objeto de exame, o Centro da cidade de Vitória, capital do Espírito Santo. A revisão bibliográfica considerou abordagens de autores contemporâneos e clássicos sobre áreas centrais, expectativas urbanísticas para o século XXI, métodos para o estudo da forma urbana e história da área em questão. A partir dessa base, foram analisados projetos urbanos e planos propostos para o Centro de Vitória no século XXI, à luz de sua problemática atual. O estudo demonstrou por um lado, complementaridade e ausência de contradições entre as proposições, a despeito de não ter havidoarticulação intencional neste sentido, e por outro, baixa efetividade de execução destas pelo poder público e consequente desatenção deste, sobre a importância da permanência de formas urbanas remotas e respectivas apropriações pela população. A conclusão aponta para o potencial dos estudos sobre a forma urbana, na perspectiva de enfrentamento dos desafios ambientais e urbanísticos do século XXI, considerando a valorização das diversas camadas históricas intrínsecas às áreas centrais, em articulação às questões sociais contemporâneas.

Objetivo: Análise das práticas regulatórias e funcionamento dos sistemas de saúde em diferentes países, com foco principal na regulação de planos de saúde vinculados ao setor privado. Método: Revisão da literatura, acrescida por informações coletadas por um desk research. A busca foi realizada na base de publicações MEDLINE, considerando publicações datadas em 2018 e 2019. Os 23 países avaliados foram organizados em cinco grupos. Resultados: Os dados apontam similitudes entre os países agrupados no que se refere às características dos sistemas de saúde e da participação do setor de saúde suplementar. Prevalecem, em âmbito global, sistemas de saúde de cobertura universal e financiados por contribuições da seguridade social e por impostos gerais. Numa parcela dos países, a participação da iniciativa privada tem caráter complementar, ofertando serviços não cobertos pelo setor público. Em outros, suplementar, ofertando serviços similares ao setor público, porém com maior oferta de prestadores. Estratégias de copagamento e utilização de listas mínimas de cobertura se mostram prevalentes. Entretanto, os mecanismos e frequências de suas atualizações são variáveis. Conclusão: A maior parte dos países analisados adota sistemas públicos e universais, que são suplementados ou complementados, de forma variável, por serviços do setor privado empresarial. Listas mínimas de cobertura e copagamento são adotadas por diversos países, de diferentes regiões. A frequência de atualização das listas é variável, sendo mais comum a atualização anual, utilizando estratégias diversas para a avaliação de tecnologias em saúde.