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UNLABELLED: On 15 January 2022, Hunga volcano erupted, creating an extensive and high-reaching umbrella cloud over the open ocean, hindering traditional isopach mapping and fallout volume estimation. In MODIS satellite imagery, ocean surface water was discolored around Hunga following the eruption, which we attribute to ash fallout from the umbrella cloud. By relating intensity of ocean discoloration to fall deposit thicknesses in the Kingdom of Tonga, we develop a methodology for estimating airfall volume over the open ocean. Ash thickness measurements from 41 locations are used to fit a linear relationship between ash thickness and ocean reflectance. This produces a minimum airfall volume estimate of 1.8-0.4+0.3 km3. The whole eruption produced > 6.3 km3 of uncompacted pyroclastic material on the seafloor and a caldera volume change of 6 km3 DRE. Our fall estimates are consistent with the interpretation that most of the seafloor deposits were emplaced by gravity currents rather than fall deposits. Our proposed method does not account for the largest grain sizes, so is thus a minimum estimate. However, this new ocean-discoloration method provides an airfall volume estimate consistent with other independent measures of the plume and is thus effective for rapidly estimating fallout volumes in future volcanic eruptions over oceans. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s00445-024-01744-6.

This laboratory experiment leverages the pedagogical value and multidisciplinary nature of biodiesel production from vegetable oil to introduce students to continuous-flow chemistry, a modern and rapidly growing approach to chemical synthesis. An interdisciplinary approach exposes students to the practical and conceptual aspects of modern continuous-flow chemistry while simultaneously reinforcing core organic chemistry techniques and investing students in issues of sustainability. Students screen reaction conditions in flow through an inquiry-guided approach and make evidence-based decisions to accomplish the sustainable conversion of waste cooking oil into biofuel. The laboratory experiment is designed to be highly modular and can be completed in two, three, five, or eight laboratory periods. By incorporating the burgeoning field of continuous-flow chemistry into the educational infrastructure, the experiments allow students to develop skills that are highly valued in the modern chemical workforce.

Self‐talk is an effective mental training technique that has been shown to facilitate or debilitate an athlete's performance, depending on its valence. Although the effects of self‐talk have been supported by observing change in sport performance, little is known about how self‐talk can induce physiological changes. Specifically, it is important to understand if the type of self‐talk (positive, neutral, or negative) and can influence stress‐related parameters, such as perceived exertion, cardiorespiratory, and cortisol responses. The study's objective was therefore to investigate the top‐down effect of positive and negative self‐talk compared to a dissociative activity during an iso‐metabolic running exercise on autonomic regulation of cardiorespiratory function. Twenty‐nine well‐trained male runners [38 ± 13 years, 177 ± 7 cm and 73 ± 7 kg] volunteered to participate in a randomized‐group design study that included a negative self‐talk (NST), a positive self‐talk, and a dissociative group (DG). First, participants underwent an incremental running test on a treadmill to determine the maximal oxygen uptake (V̇O2max). Next, participants received a mental training session on self‐talk and created three positive and three negative self‐talk statements. Finally, participants underwent a 60‐min steady‐state running exercise on a treadmill at 70% of V̇O2max, during which they were cued at 20‐, 35‐, and 50‐min with their personal self‐created positive or negative self‐talk statements while the DG listened to a documentary. Cardiorespiratory parameters and rate of perceived exertion (RPE) were recorded throughout the 60‐min endurance exercise. In addition, salivary cortisol samples were obtained at waking and after treatment. Although oxygen uptake, carbon dioxide production, RPE, and heart rate significantly changed overtime during the 60‐min steady‐state running exercise, no significant main treatment effect was found. However, RPE scores, minute ventilation, breathing frequency, and salivary cortisol were significantly higher in the NST group compared to the two other groups. These data suggest that NST [emotion‐induced stress, as reflected by elevated cortisol] altered the breathing frequency response. In conclusion, manipulating self‐talk alters hormonal response patterns, modulates cardiorespiratory function, and influences perceived exertion. To date, there have been no studies specifically designed to explore the neural functional connections that would specifically elucidate the top‐down neurophysiological pathway associating self‐talk during exercise. This study demonstrates that emotion‐induced stress alters the neural functional connections as reflected in cardiovascular and hormonal responses. [ABSTRACT FROM AUTHOR]

• Policies that support physical activity (PA) in the school-setting have promise but their impact is poorly understood. • Nine policy action areas for which there was evidence of impact were identified. These were whole-school PA policy, physical education, sport/extracurricular PA, classroom-based PA, active breaks, physical environment, shared use agreements, active school transport and surveillance. • Evidence supports the effectiveness of PA policy actions within the school-setting but cautions a "one-size fits all" approach. • Further evaluation of policy implementation to maximize translation into practice is required. • Greater clarity regarding terminology, measurement, and methods for evaluation of policy interventions is needed, and suggestions provided. Despite the well-established health benefits of physical activity (PA) for young people (aged 4–19 years), most do not meet PA guidelines. Policies that support PA in schools may be promising, but their impact on PA behavior is poorly understood. The aim of this systematic review was to ascertain the level and type of evidence reported in the international scientific literature for policies within the school setting that contribute directly or indirectly to increasing PA. This systematic review is compliant with Preferred Reporting Items for Systematic Review and Meta-Analysis guidelines. Six databases were searched using key concepts of policy, school, evaluation, and PA. Following title and abstract screening of 2323 studies, 25 progressed to data synthesis. Methodological quality was assessed using standardized tools, and the strength of the evidence of policy impact was described based on pre-determined codes: positive, negative, inconclusive, or untested statistically. Evidence emerged for 9 policy areas that had a direct or indirect effect on PA within the school setting. These were whole school PA policy, physical education, sport/extracurricular PA, classroom-based PA, active breaks/recess, physical environment, shared use agreements, active school transport, and surveillance. The bulk of the evidence was significantly positive (54%), 27% was inconclusive, 9% was significantly negative, and 11% was untested (due to rounding, some numbers add to 99% or 101%). Frequency of evidence was highest in the primary setting (41%), 34% in the secondary setting, and 24% in primary/secondary combined school settings. By policy area, frequency of evidence was highest for sport/extracurricular PA (35%), 17% for physical education, and 12% for whole school PA policy, with evidence for shared use agreements between schools and local communities rarely reported (2%). Comparing relative strength of evidence, the evidence for shared use agreements, though sparse, was 100% positive, while 60% of the evidence for whole school PA policy, 59% of the evidence for sport/extracurricular PA, 57% of the evidence for physical education, 50% of the evidence for PA in classroom, and 50% of the evidence for active breaks/recess were positive. The current evidence base supports the effectiveness of PA policy actions within the school setting but cautions against a "one-size-fits-all" approach and emphasizes the need to examine policy implementation to maximize translation into practice. Greater clarity regarding terminology, measurement, and methods for evaluation of policy interventions is needed. [Display omitted] [ABSTRACT FROM AUTHOR]

As a demonstration of an alternative to the challenges faced with batch pharmaceutical manufacturing including the large production footprint and lengthy timescale, we previously reported a refrigerator-sized continuous flow system for the on-demand production of essential medicines. Building on this technology, herein we report a second-generation, reconfigurable and 25% smaller (by volume) continuous flow pharmaceutical manufacturing platform featuring advances in reaction and purification equipment. Consisting of two compact [0.7 (L) Χ 0.5 (D) Χ 1.3m (H)] stand-alone units for synthesis and purification/ formulation processes, the capabilities of this automated system are demonstrated with the synthesis of nicardipine hydrochloride and the production of concentrated liquid doses of ciprofloxacin hydrochloride, neostigmine methylsulfate and rufinamide that meet US Pharmacopeia standards. [ABSTRACT FROM AUTHOR]

Magnetic iron oxide (Magnetite, Fe3O4) nanoparticles are widely utilized in magnetic resonance imaging (MRI) and drug delivery applications due to their superparamagnetism. Surface coatings are often employed to change the properties of the magnetite nanoparticles or to modulate their biological responses. In this study, magnetite nanoparticles were fabricated through hydrothermal synthesis. Hydrophobicity is often increased by surface modification with oleic acid. In this study, however, hydrophobicity was introduced through surface modification with n-octyltriethoxysilane. Both the uncoated (hydrophilic) and coated (hydrophobic) individual nanoparticle sizes measured below 20 nm in diameter, a size range in which magnetite nanoparticles exhibit superparamagnetism. Both types of nanoparticles formed aggregates which were characterized by SEM, TEM, and dynamic light scattering (DLS). The coating process significantly increased both individual particle diameter and aggregate sizes. We tested the neurotoxicity of newly synthesized nanoparticles with two mammalian cell lines, PC12 (rat pheochromocytoma) and ReNcell VM (human neural stem cells). Significant differences were observed in cytotoxicity profiles, which suggests that the cell type (rodent versus human) or the presence of serum matters for nanoparticle toxicology studies. Differences in nanoparticle associations/uptake between the two cell types were observed with Prussian Blue staining. Finally, safe concentrations which did not significantly affect neuronal differentiation profiles were identified for further development of the nanoparticles. [ABSTRACT FROM AUTHOR]