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Weight reduction in material extrusion composite parts: pin-bearing behavior analysis
No full textThis study investigated the performance of lightweight samples in pin-bearing tests. The samples were manufactured through Material Extrusion technology of nylon reinforced with short carbon fibers. Their design was based on infill strategy, density, and raster angle. Load–displacement curves and failure mechanisms were analyzed across configurations, with statistical methods applied to evaluate the influence of design factors on maximum stress, relative displacement, and stiffness. Results reveal distinct load–displacement behaviors and failure mechanisms, with deposition strategies tailored to specific final purposes. Specifically, the study identifies gyroid infill, 50% density, and a raster angle of 45° as the optimal solution for maximizing bearing stress. This configuration exhibits a weight and printing time reduction of 40% and 8% concerning the full sample, and a performance reduction in the range of 30–56%, considering both stress (28.2 MPa vs 65.8 MPa) and displacement reduction (9.4 mm vs 15.1 mm). Conversely, rectangular infill, 50% density and raster angle of 0° emerge as the optimal solution for minimizing displacement and maximizing stiffness. This configuration exhibits a weight and printing time reduction of 39% and 34%, in comparison to the full sample, and a performance reduction of about 65–70% (displacement of 4.6 mm at a maximum stress of 23.7 MPa). The triangular strategy can be used to reach elevated values for all output parameters (up to 25.9 MPa as maximum stress, 9.4 mm as maximum displacement, and 242.4 MPa for stiffness), with weight and printing time saving in the range of 41–54% and 34–36% respectively
Accelerated carbonation of municipal waste fly ash for carbon sequestration: a review
No full textThe accelerating climate change requires rapid techniques to both sequester carbon dioxide and recycle solid waste. Here we review the accelerated carbonation of fly ash from municipal solid waste with emphasis on carbonation methods, carbon dioxide sequestration capability, influence of carbonation on fly ash properties, fly ash as a cementitious material, non-conventional uses of fly ash, environmental and economic benefits, mixing with other waste materials, pilot and industrial applications, and limitations. We observe that the accelerated carbonation of fly ash allows for carbon dioxide capture of up to 0.24 g CO2 per gram of ash, reduces heavy metal leaching, facilitates the reuse of stabilized ashes, and generates materials suitable for a wide range of uses. Limitations include possible pH-induced remobilization of toxic metals such as cadmium, chromium, and antimony
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No full textTNF Production or TNFR2 Expression Characterize Distinct States of Regulatory T Cells that Cooperate in Treg Expansion in Cancer and Chronic Inflammation
Full text linkTNF is a pleiotropic cytokine with immunomodulatory functions mediated by its interaction with the receptor TNFR2, highly expressed by Tregs. However, Tregs can also produce TNF, and an autocrine TNF-TNFR2 loop has been proposed. Here, we describe that both human and mouse Tregs produce TNF in physiological conditions, in several mouse organs, and in mouse models of chronic inflammation and cancer. However, TNF production and TNFR2 expression are differentially distributed: indeed, TNFR2+ and TNFR2− Treg subsets are, respectively, poor and strong TNF producers. The two subsets of TNFR2+ and TNFR2− Tregs partially maintain their different ability to produce TNF when separately stimulated ex vivo. However, when cocultured, the TNFR2+ cells greatly outnumber the TNFR2− counterpart and induce in TNFR2− cells the upregulation of Foxp3 and TNFR2, in association with the transfer of cytoplasmic material. Functionally, TNFR2+ Tregs display superior suppressive activity and survival in vitro, both related to an improved resistance to oxidative stress. Overall, our data indicate that Tregs exist in two states, respectively committed to TNF production or TNF sensing through TNFR2, which cooperate in promoting the suppressive function of the whole Treg pool
Open repair of native and prosthetic aortic infection with pre-sutured or stapled xenopericardial grafts
No full textBackground: Aortic Graft Infection (AGI) and Infective Native Aortic Aneurysm (INAA) require open repair with infection-resistant prostheses. Physician’s made xeno-pericardial grafts combine availability with freedom from reinfection, but mainly short-term results are reported. The aim is to examine the mid-term outcomes in aortic infections using stapled physician-made or pre-sutured bovine pericardium tube grafts. Methods: We report all patients who underwent in situ aortic reconstruction using pericardial tube grafts (prepared from pericardial patches using a surgical stapler or pre-sutured) for AGI or INAA between January 2019 and October 2024 at a single center. Perioperative outcomes and follow-up data were retrospectively collected. Results: Twenty-one patients (18 male, median age 72 years) underwent aortic surgery and implantation of a preformed (N.=5) or stapled physician-made (N.=16) pericardial tubes graft for an INAA (N.=7) or AGI (N.=14). All AGI patients had late infections (median time from primary surgery of 81 months), in nine cases associated with aorto-digestive fistula. One perioperative death was recorded. Patients treated for an AGI demonstrated a longer median length of stay (22 vs. 12 days; P=0.020) and higher intraoperative blood loss (1400 vs. 400 mL; P=0.025). Of the 20 patients surviving the index event, at a mean follow-up of 23±8 months, no aortic-related death, nor mechanical failure were recorded. One case of reinfection and reintervention has been observed (4.8%). All but one patient discontinued the antibiotic therapy after a median duration of 146 days. Conclusions: Aortic repair with preformed and home-made stapled xeno-pericardial grafts is safe and provides durable infection-free survival at a mid-term follow-up
Surface modification of nanocatalysts via ion beam techniques for enhanced activity
Full text linkInterface science is at the forefront of advanced materials design, particularly in catalysis, where surface properties critically determine performance. Among emerging techniques, ion beam irradiation has shown strong potential for modifying the catalytic behavior of solid materials by introducing surface and sub-surface defects. In this study, the effect of nitrogen ion irradiation on the catalytic and redox properties of a ceria-zirconia-based oxidation catalyst (Ce0.68Zr0.32O2), both in its unmodified form and when combined with supported Pt nano-particles, was systematically investigated through a series of catalytic tests (TPO/TPR), operando FTIR, HRTEM, and XPS analyses. Ion bombardment was found to induce significant modifications to nanoparticle distribution, surface morphology, and defect structure-most notably the formation of oxygen vacancies and enhanced oxygen mobility. These changes resulted in improved catalytic performance for the oxidation of light alkanes and CO, with consistent reductions in To0 values and a notable increase in aging resistance. The enhanced reducibility observed, particularly in Pt-containing systems, suggests a strong impact at the metal/support interface. Overall, this work highlights post-synthesis ion irradiation as an effective tool for activating and stabilizing redox catalysts, providing new opportunities for designing durable materials for environmental and energy applications
Aggressive B cell lymphomas retain ATR-dependent determinants of T cell exclusion from the germinal center dark zone
No full textThe germinal center (GC) dark zone (DZ) and light zone represent distinct anatomical regions in lymphoid tissue where B cell proliferation, immunoglobulin diversification, and selection are coordinated. Diffuse large B cell lymphomas (DLBCLs) with DZ-like gene expression profiles exhibit poor outcomes, though the reasons are unclear and are not directly related to proliferation. Physiological DZs exhibit an exclusion of T cells, prompting exploration of whether T cell paucity contributes to DZ-like DLBCL. We used spatial transcriptomic approaches to achieve higher resolution of T cell spatial heterogeneity in the GC and to derive potential pathways that underlie T cell exclusion. We showed that T cell exclusion from the DZ was linked to DNA damage response (DDR) and chromatin compaction molecular features characterizing the spatial DZ signature, and that these programs were independent of activation-induced cytidine deaminase (AID) activity. As ATR is a key regulator of DDR, we tested its role in the T cell inhibitory DZ transcriptional imprint. ATR inhibition reversed not only the DZ transcriptional signature, but also DZ T cell exclusion in DZ-like DLBCL in vitro microfluidic models and in in vivo samples of murine lymphoid tissue. These findings highlight that ATR activity underpins a physiological scenario of immune silencing. ATR inhibition may reverse the immune-silent state and enhance T cell–based immunotherapy in aggressive lymphomas with GC DZ–like characteristics
European Laryngological Society consensus statement on optimal monitoring schedules after treatment for early glottic cancer: a risk-stratification
No full textEarly glottic cancer has an excellent prognosis provided that recurrences are detected in a timely manner. However, current guidelines lack specific recommendations for intervals or interventions during follow-up, and primarily advocate surveillance in the most advanced stages where the benefits are actually the lowest. This consensus statement introduces a risk-stratification-guided follow-up schedule for T1-T2N0 patients, aiming to optimize oncologic and functional outcomes while ensuring early detection of residual or recurrent disease to preserve organ function. Separate protocols are outlined for surgical and non-surgical patients, including endoscopic examination, radiological imaging, and thyroid function screening. Also, the pathway to reach this routine observation phase is described, specifying the criteria and timing of a second-look microlaryngoscopy