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3D silicon oxycarbide structures fabricated by digital light processing 3D printing of preceramic polymers derived from sol-gel synthesis of selected siloxane precursors
No full textRecent studies have reported the fabrication of Polymer-Derived Ceramics (PDCs) materials using Digital Light Processing
(DLP). However, these works primarily employed commercially available preceramic polymers (PCPs). In contrast, in
this study we took a step back and started with siloxane precursors to gain strict control over chemical composition and
microstructure, and consequently the properties of the final materials. We present a novel approach for the fabrication of
3D silicon oxycarbide (SiOC) structures. The PCPs was prepared by sol-gel synthesis using siloxane precursors. Specifically,
ladder-like polysiloxanes were synthesized with methacrylate groups introduced into their structure. An efficient
photocurable system was developed by mixing the polysiloxane sol with 1-phenyl-1,2-propanedione (PPD) as the photoinitiator
and ethyl 4-(dimethylamino)benzoate (EDMAB) as the co-initiator. Following the DLP fabrication, the resulting
3D PCPs structures were converted into final SiOC elements by pyrolysis in an inert atmosphere. Detailed microstructural
and structural analyses of the resulting materials are provided
Bioresorbable vascular scaffold versus metallic drug-eluting stent in patients at high risk of restenosis : final 7-year results of the COMPARE-ABSORB trial
No full text200 J-first, fixed-escalation biphasic electrical cardioversion for atrial fibrillation >48 hours in the emergency department : a single-centre retrospective observational study
No full textPorphyromonas gingivalis vesicles control osteoclast–macrophage lineage fate
No full textPorphyromonas gingivalis (Pg), a keystone pathogen of chronic periodontitis, releases outer membrane vesicles (OMVs) that act as nanoscale vehicles to disseminate virulence factors within periodontal tissues and systemically beyond the oral cavity. Although Pg-OMVs are increasingly recognized as critical mediators of host–pathogen interactions, their effects on the differentiation and function of monocyte–macrophage/osteoclast lineage cells remain unclear. Here, we examined the impact of Pg-OMVs on the differentiation of RAW264.7 monocyte/macrophage-like cells into osteoclasts (OC) and/or macrophages (MΦ) in the presence of receptor activator of nuclear factor-κB ligand (RANKL). OMVs were isolated from Pg W83 and applied to RANKL-primed RAW264.7 cells using three distinct stimulation schedules: (1) simultaneous treatment with Pg-OMVs and RANKL at Day 0; (2) RANKL priming at Day 0 followed by Pg-OMV stimulation at Day 1; and (3) RANKL priming at Day 0 followed by Pg-OMV stimulation at Day 3. In all schedules, cells were cultured for 7 days from the initial RANKL exposure. Remarkably, simultaneous exposure to Pg-OMVs and RANKL (Schedule 1) markedly suppressed osteoclastogenesis (OC-genesis) while promoting M1 macrophage polarization. In contrast, delayed Pg-OMV stimulation of RANKL-primed cells (Schedules 2 and 3) significantly enhanced OC-genesis while reducing M1 polarization. These schedule-dependent effects were consistent with altered expression of osteoclastogenic markers, including dc-stamp, oc-stamp, nfatc1, and acp5. Importantly, a monoclonal antibody against OC-STAMP counteracted the Pg-OMV-induced upregulation of OC-genesis in Schedules 2 and 3. Furthermore, levels of Pg-OMV phagocytosis were inversely correlated with osteoclast formation. Finally, co-stimulation with RANKL and Pg-OMVs (Schedule 1) enhanced macrophage migratory capacity, whereas delayed stimulation with Pg-OMVs (Schedules 2 and 3) did not. Collectively, these findings indicate that Pg-OMVs exert stage-specific effects on the OC/MΦ lineage: stimulation at early stages of RANKL priming suppresses OC-genesis and promotes M1 polarization, whereas stimulation at later stages enhances OC-genesis without inducing M1 differentiation. Thus, Pg-OMVs may critically influence the fate of the OC/MΦ unit in periodontal lesions, contributing to disease progression and tissue destruction
Iron-modified dendritic mesoporous silica nanoparticles as catalysts for propane and ethane oxidative dehydrogenation
No full textFirst results on the search for lepton number violating neutrinoless double- decay with the LEGEND-200 experiment
No full textThe LEGEND Collaboration is searching for neutrinoless double-beta () decay by operating high-purity germanium detectors enriched in Ge in a low-background liquid argon environment. Building on key technological innovations from the GERmanium Detector Array (GERDA) experiment and the MAJORANA DEMONSTRATOR experiment, LEGEND-200 has performed a first decay search based on 61.0 kg yr of data. Over half of this exposure comes from our highest performing detectors, including newly developed inverted-coaxial detectors, and is characterized by an estimated background level of 0.5 cts/(keV ton yr) in the decay signal region. A combined analysis of data from GERDA, the MAJORANA DEMONSTRATOR, and LEGEND-200, characterized by a 90% confidence level exclusion sensitivity of 2.8 10 yr on the half-life of decay, reveals no evidence for a signal and sets a new observed lower limit at > 1.0 10 yr (90% confidence level). Assuming the decay is mediated by Majorana neutrinos, this corresponds to an upper limit on the effective Majorana mass in the range < 75-200 meV, depending on the adopted nuclear matrix element