Riley Paulsen (jammask61)

This study presents a novel and facile strategy for fabricating fire-resistant, ultraviolet (UV)-shielding, and tensile-enhanced polylactide (PLA) composites using two-dimensional (2D) MXene (Ti3C2) flakes chemically modified with 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO). PRGL493 The thermal and burning performances of PLA composites were demonstrated by the limiting oxygen index, UL-94 test, and cone calorimetry. The UV-shielding and tensile performances were also examined. The results revealed that PLA/Ti3C2-DOPO (3 wt %) displayed a V-0 rating in the UL-94 test. The enhancement against fire hazard was reflected by the significant reduction in the peak heat release rate (33.7%), total heat release (47%), peak CO production (58.8%), and total smoke production (41.7%). The improved fire-safety performance of the composites is attributed to the interplay of catalytic, barrier, and condensed effects of the Ti3C2-DOPO nanosheets in the PLA matrix. PLA/Ti3C2-DOPO also showed an increase (∼9%) in tensile strength and an "Excellent" level (UPF 50+) in the UV-protection assessment. In all, this study introduces a novel chemical modification strategy for 2D MXene flakes to fabricate multifunctional PLA composites, which are promising candidates for next-generation sustainable and protective plastic products.Protein-lipid interactions govern the structure and function of lipoprotein particles, which transport neutral lipids and other hydrophobic cargo through the blood stream. Apolipoproteins cover the surface of lipoprotein particles, including low-density (LDL) and high-density (HDL) lipoproteins, and determine their function. Previous work has focused on small peptides derived from these apolipoproteins or used such artificial lipid systems as Langmuir monolayers or the lipid disc assay to determine how apolipoproteins interact with the neutral lipid interface. Here, we focus on a recurring protein domain found in many neutral lipid-binding proteins, the amphipathic α-helix bundle. We use liquid droplet tensiometry to investigate protein-lipid interactions on an oil droplet, which mimics the real lipoprotein interface. The N-terminus of apoE 3 and full-length apoLp-III serve as model proteins. We find that each protein interacts with lipid monolayers at the oil-aqueous interface in unique ways. For the first time, we show that helix bundle unfolding is critical for proper protein insertion into the lipid monolayer at the oil-aqueous interface and that specific membrane lipids promote the rebinding of protein upon fluctuation in droplet size. These results shed new light on how amphipathic apolipoprotein α-helix bundles interact with neutral lipid particles.Since 2001, four emission measurement campaigns have been conducted in multiple traffic tunnels in the megacity of São Paulo, Brazil, an area with a fleet of more than 7 million vehicles running on fuels with high biofuel contents gasoline + ethanol for light-duty vehicles (LDVs) and diesel + biodiesel for heavy-duty vehicles (HDVs). Emission factors for LDVs and HDVs were calculated using a carbon balance method, the pollutants considered including nitrogen oxides (NOx), carbon monoxide (CO), and sulfur dioxide, as well as carbon dioxide and ethanol. From 2001 to 2018, fleet-average emission factors for LDVs and HDVs, respectively, were found to decrease by 4.9 and 5.1% per year for CO and by 5.5 and 4.2% per year for NOx. These reductions demonstrate that regulations for vehicle emissions adopted in Brazil in the last 30 years improved air quality in the megacity of São Paulo significantly, albeit with a clear delay. These findings, especially those for CO, indicate that official emission inventories underestimate vehicle emissions. Here, we demonstrated that the adoption of emission factors calculated under real-world conditions can dramatically improve air quality modeling in the region.The sensitive and selective detection of biomarkers for human health r