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This study investigates the development of polypropylene (PP) nanocomposites reinforced with graphene nanoplatelets (GNPs) and glass fibers (FGs), focusing on the evaluation of their morphological, thermal, and mechanical properties. Through twin-screw and single-screw extrusion processes followed by injection, we explore the influence of different GNP concentrations (0, 0.125, and 0.5 wt%) and the addition of glass fibers (20, 40, and 60 wt%) on the PP matrix. The results indicate that the careful incorporation of GNP and glass fibers not only significantly enhances the mechanical strength and thermal deflection temperature of the nanocomposites but also affects crystallinity and thermal conductivity in predictable and beneficial ways. Particularly, nanocomposites containing 0.125% GNP and 40% glass fibers exhibited an increase of 254.1% in tensile strength and 243.2% in flexural strength compared to pure PP, highlighting the potential of these materials in high-performance engineering applications. This work not only advances knowledge in the area of polymer nanocomposites but also demonstrates the practical potential of hybrid materials in overcoming the limitations of conventional materials, opening new perspectives for their application in critical sectors such as automotive, aerospace, and construction. [ABSTRACT FROM AUTHOR]

Research on the use of sustainable fillers which promote improvements in the paints has been reported over the years. The present study investigated the production and characterization of a biochar produced from Pinus elliottii for application in an epoxy paint cured by ultraviolet radiation, comparing it with graphite, in proportions of 12.5 and 20 wt%. The Pinus elliottii sample was initially ground, and then submitted to physical and morphological characterization by field emission scanning electron microscopy (SEM) and X-ray diffraction (XRD). Later, the Pinus elliottii sample was subjected to pyrolysis at a temperature of 1050°C at a low heating rate (5°C/min). Biochar and graphite were separately incorporated into an epoxy UV-curable paint. The painted samples had their thickness measured and their mechanical and physical properties evaluated, namely gloss, hardness, bending, impact, contact angle with water, and exposure to salt spray. Biochar and graphite promoted a reduction in gloss and improved pencil hardness when incorporated into a UV-curable epoxy paint. In the salt spray resistance test, samples containing both biochar and graphite showed a slight delay in the beginning of the corrosion process. However, samples with biochar behaved better than samples with graphite in terms of blistering of the film in the incision region. [ABSTRACT FROM AUTHOR]

Graphene nanoplatelets (GNP) have excellent properties, such as high mechanical strength and good thermal conductivity, making them interesting nanofiller for their application in powder coatings. In this context, the aim of this study was to evaluate the thermal behavior and the curing kinetics of epoxy powder coatings containing GNP. The coatings were obtained by mixing in a ball mill followed by homogenization in molten state. The GNP were dispersed directly into the epoxy powder. The morphology, thermal stability and curing kinetics of the samples were evaluated. During the curing process, the GNP accelerated the onset of the reaction but ultimately caused steric impediment. From the results, the GNP incorporated to the solid epoxy resin for coatings behaved differently in each stage of the curing process. In general, while the direct dispersion of GNP in powder epoxy by dry mixing methods was not ideal, the thermal properties were improved, with GNP inducing a poor curing state where diffusion phenomena are predominant. [ABSTRACT FROM AUTHOR]

Introduction: The incidence of anastomotic leak (AL) has not decreased over the past decades and some important grey areas remain in its definition, prevention, and management. The aim of this study was to reach a national consensus on the definition of AL and to identify key points to be applied in clinical practice. Methods: A 3-step modified Delphi method was used to establish consensus. Ten representative members of the major Italian surgical scientific societies with proven colorectal expertise were selected after a call to action. After a comprehensive literature search, each expert drew a list of evidence-based statements which were voted in round one by the scientific board. Panel members were asked to mark "totally disagree", "partially agree" or "totally agree" for each statement and provide comments. The same voting method was used for round 2. Round 3 consisted of a final face-to-face meeting. Results: Thirty-three statements (clustered into 14 topics) were included in round 1. Following the third voting round, a final list of 16 items was formulated, which encompass the following 9 topics: AL definition, patient- and operative-related risk factors, prevention measures, bowel preparation, surgical technique, intraoperative assessment, early diagnosis, radiological diagnosis and management of specific patterns of AL. The overall response rate was 100% for all items in all the three rounds. Conclusions: This Delphi survey identified items that expert colorectal surgeons agreed were important to be applied in the prevention, diagnosis, and management of AL. This represents the first consensus involving all relevant national scientific societies, defining important and shared concepts in the diagnosis and management of AL. [ABSTRACT FROM AUTHOR]

Endovascular treatment options for visceral artery pseudoaneurysms depend on lesion location and size. Exclusion methods fall into two categories, embolization and stent placement, and these procedures aim to exclude the pseudoaneurysm from the circulation and if possible to maintain distal blood flow. Embolization of the afferent artery can be used in pseudoaneurysms that arise from a donor artery without collateral supply such as a visceral branch, whereas in the case of visceral arteries with well-established collateral supply, the embolization of both proximal and distal branches to the pseudoaneurysm is mandatory in preventing backflow from the collateral circulation. A direct embolization delivering coils or glue into the sac can also be performed if the aneurismal neck is narrow. Stent-graft placement represents another option to exclude the pseudoaneurysm, in the case of wide neck, reduced arterial tortuosity and large-diameter arteries. We present a case of common hepatic artery pseudoaneurysm involving the gastroduodenal artery origin treated by a combination of techniques. An hepatic stent-graft implantation plus retrograde embolization of the gastroduodenal artery through the pancreaticoduodenal anastomosis from the superior mesenteric artery was performed. [ABSTRACT FROM AUTHOR]