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The Salmon River Coloring Book documents patterns of algal succession found on the Salmon River in northern California (a tributary to the larger Klamath River) which includes diatoms, cyanobacteria, and green algae. Algal groups are presented in coloring pages as both (1) macroscopic (i.e., visible to the human eye) forms and (2) microscopic (i.e., requiring a microscope) forms. On each page, rhyming text accompanies the line art to provide further educational information about each algal group. To aid in the coloring process, we also created a reference that provides actual photos from both the field and microscope. This work was hand-drawn in digital art applications and written by both Jordan Zabrecky and Taryn Elliott who both collected algal samples on the Salmon River in the summer of 2023 supported by Nation Science Foundation Division of Biology Grant Award #2042915. Access link: https://oercommons.org/courseware/lesson/141536 

We quantify volatile organic compound (VOC) emissions from indoor surface swabs and portable air cleaner (PAC) filters collected in a home thirty days after the 2025 Los Angeles wildland-urban interface (WUI) fires. We calculate emissions for seventeen fire-relevant compounds. Surface emissions exceeded those of clean controls, and emissions from a windowsill in a room without a PAC were ~15× and ~2× higher for benzene and toluene, respectively, than rates reported in the literature for comparable materials unaffected by smoke/soot. Particle filters in PACs installed at the start of the fire emitted aromatics at rates comparable to those reported in a study where filters operated for 200 days in a city; emissions from activated carbon filters exceeded by >10× those of the particle filter. A windowsill in a room without a PAC off-gassed more VOC mass than a windowsill in a room with a PAC, suggesting that air cleaners can reduce surface contamination. Modeling with benzene emission rates from impacted surfaces in a hypothetical indoor space resulted in a predicted indoor concentration ~6× greater than outdoors. This study shows surfaces act as persistent VOC sources following WUI fires and indicates indoor surfaces affect exposure during and after fire events. 

In this study, we examine the performance of a multi-scale model for large-eddy simulation (LES) of tur- bulent combustion. The model referred to as RRLES performs the closure of the filtered reaction-rate term in the species transport equation while performing LES by using the linear eddy mixing (LEM) model. The RRLES model uses a multi-scale strategy to obtain the filtered reaction rate of the species and has been shown to address some of the challenges associated with the well-established LEMLES approach. The orig- inally proposed RRLES strategy used a multilevel adaptive mesh refinement (AMR) framework, which was extended to use a single grid-based strategy to enable the application to complex geometries. Additionally, a local dual-resolution grid strategy has also been developed and can potentially be used with different grid topologies, without the need for the AMR. We assess the accuracy and efficiency of the single and dual-grid RRLES approaches by considering a freely propagating turbulent premixed flame under two different initial conditions corresponding to the thin reaction zone (TRZ) and the broken/distributed reaction zone (B/DRZ) regimes. 

Building insulation materials can affect indoor air by (i) releasing primary volatile organic compounds (VOCs) from building enclosure cavities to the interior space, (ii) mitigating exposure to outdoor pollutants through reactive deposition (of oxidants, e.g. , ozone) or filtration (of particles) in infiltration air, and (iii) generating secondary VOCs and other gas-phase byproducts resulting from oxidant reactions. This study reports primary VOC emission fluxes, ozone (O 3 ) reaction probabilities ( γ ), and O 3 reaction byproduct yields for eight common, commercially available insulation materials. Fluxes of primary VOCs from the materials, measured in a continuous flow reactor using proton transfer reaction-time of flight-mass spectrometry, ranged from 3 (polystyrene with thermal backing) to 61 (cellulose) μmol m −2 h −1 (with total VOC mass emission rates estimated to be between ∼0.3 and ∼3.3 mg m −2 h −1 ). Major primary VOC fluxes from cellulose were tentatively identified as compounds likely associated with cellulose chemical and thermal decomposition products. Ozone-material γ ranged from ∼1 × 10 −6 to ∼30 × 10 −6 . Polystyrene with thermal backing and polyisocyanurate had the lowest γ , while cellulose and fiberglass had the highest. In the presence of O 3 , total observed volatile byproduct yields ranged from 0.25 (polystyrene) to 0.85 (recycled denim) moles of VOCs produced per mole of O 3 consumed, or equivalent to secondary fluxes that range from 0.71 (polystyrene) to 10 (recycled denim) μmol m −2 h −1 . Major emitted products in the presence of O 3 were generally different from primary emissions and were characterized by yields of aldehydes and acetone. This work provides new data that can be used to evaluate and eventually model the impact of “hidden” materials ( i.e. , those present inside wall cavities) on indoor air quality. The data may also guide building enclosure material selection, especially for buildings in areas of high outdoor O 3 .