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ABSTRACT Air mass source regions and meteorological factors significantly influenced aerosol loading along air mass trajectories over Boone, North Carolina, between June 1, 2023, to August 31, 2023. This study examines the impact of northeast Canadian wildfires on aerosol loading, quantified by the particle light scattering coefficients at 550 nm measured at the NOAA Federated Aerosol Monitoring site at Appalachian State University (APP). Using NOAA’s HYSPLIT trajectory model, hourly back trajectories originating at 500 meters above ground level at APP were analyzed over a 96-hour timespan and categorized into four aerosol loading classifications based on the aerosol light scattering coefficient at 550 nm measured at APP. All air parcel trajectories originating in eastern Canada were associated with the high and very high aerosol load classifications. Statistical analysis shows that wildfire-sourced parcels exhibit elevated temperatures and variability in solar flux. The findings establish a link between Canadian wildfire activity and increased aerosol loading in Boone, NC, emphasizing the relationships between source region, transport dynamics, and atmospheric conditions. These results provide a framework for further exploration of aerosol source regions and their broader environmental impacts. 

The thermal conductivities of (100) γ-Ga2O3 films deposited on (100) MgAl2O4 substrates with various thicknesses were measured using frequency-domain thermoreflectance. The measured thermal conductivities of γ-Ga2O3 films are lower than the thermal conductivities of (2¯ 01) β-Ga2O3 films of comparable thickness, which suggests that γ-phase inclusions in the doped or alloyed β-phase may affect its thermal conductivity. The thermal conductivity of γ-Ga2O3 increases from 2.3−0.5+0.9 to 3.5±0.7 W/m K for films with thicknesses of 75–404 nm, which demonstrates a prominent size effect on thermal conductivity. The thermal conductivity of γ-Ga2O3 also shows a slight increase as temperature increases from 293 to 400 K. This increase in thermal conductivity occurs when defect and boundary scattering suppress signatures of temperature-dependent Umklapp scattering. γ-Ga2O3 has a cation-defective spinel structure with at least two gallium vacancies in every unit cell, which are the likely source of defect scattering. 

Abstract Nature‐inspired functional surfaces with micro‐ and nanoscale features have garnered interest for potential applications in optics, imaging, and sensing. Traditional fabrication methods, such as lithography and self‐assembly, face limitations in versatility, scalability, and morphology control. This study introduces an innovative technology, condensed droplet polymerization (CDP), for fabricating polymeric micro‐ and nano‐dome arrays (PDAs) with readily tunable geometric properties—a challenging feat for conventional methods. The CDP process leverages free‐radical polymerization in condensed monomer droplets, allowing rapid production of PDAs with targeted sizes, radii of curvature, and surface densities by manipulating a key synthesis parameter: the temperature of a filament array that activates initiators. This work systematically unravels its effects on polymerization kinetics, viscoelastic properties of the polymerizing droplets, and geometric characteristics of the PDAs. Utilizing in situ digital microscope, this work reveals the morphological evolution of the PDAs during the process. The resulting PDAs exhibit distinct optical properties, including magnification that enables high‐resolution imaging beyond the diffraction limit of conventional microscopes. This work demonstrates the ability to magnify and focus light, enhancing imaging of subwavelength structures and biological specimens. This work advances the understanding of polymerization mechanisms in nano‐sized reactors (i.e., droplets) and paves the way for developing compact optical imaging and sensing technologies. 

The Bear Valley Formation (Fm.) is a distinctive eolian sandstone interbedded with thick volcanic rocks of the Marysvale volcanic field of southwest Utah, the southern part of which failed during eruptive activity along three mega-scale gravity slides. The formation is as thick as 300 m and extends over an area of >2,500 km²in the Black Mountains and Markagunt Plateau. The Bear Valley Fm. is composed of tuffaceous sandstone interbedded with tuff, conglomerate, and polymict volcanic mudflow breccias. The sandstone beds are lithic arenite and lithic wacke that occur as massive beds with large-scale cross bedding. The Bear Valley Fm. occurs in the upper plate of the Markagunt gravity slide and is in both the upper and lower plates of the Black Mountains gravity slide. We used laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) to acquire U/Pb dates of detrital zircons (N = 3, n = 346) from the autochthonous Bear Valley Fm. at Kane Spring and Jako Wash in the Black Mountains and the allochthonous Bear Valley at Sandy Wash in the central Markagunt Plateau. All samples are dominated by Oligocene zircons with maximum likelihood ages for deposition ranging from 23.6 to 24.0 Ma. The western-most sample from Jako Wash also preserves a slightly older group of zircons, indicating derivation from either the underlying Wah Wah Springs Fm. or another unit erupted from the Indian Peak caldera complex to the west. Thus, the upper Bear Valley Fm. was deposited within ~400 kyr before the emplacement of the Markagunt gravity slide at 23 Ma, reflecting accelerated uplift of the northern Marysvale complex that ultimately resulted in collapse and slide emplacement. 

Autologous photoreceptor cell replacement is one of the most promising strategies currently being developed for the treatment of patients with inherited retinal degenerative blindness. Induced pluripotent stem cell–derived (iPSC-derived) retinal organoids, which faithfully recapitulate the structure of the neural retina, are an ideal source of transplantable photoreceptors required for these therapies. However, retinal organoids contain other retinal cell types, including bipolar, horizontal, and amacrine cells, which are unneeded and may reduce the potency of the final therapeutic product. Therefore, approaches for isolating fate-committed photoreceptor cells from dissociated retinal organoids are desirable. In this work, we present partial dissociation, a technique that leverages the high level of organization found in retinal organoids to enable selective enrichment of photoreceptor cells without the use of specialized equipment or reagents such as antibody labels. We demonstrate up to 90% photoreceptor cell purity by simply selecting cell fractions liberated from retinal organoids during enzymatic digestion in the absence of mechanical dissociation. Since the presented approach relies on the use of standard plasticware and commercially available current good manufacturing practice–compliant reagents, we believe that it is ideal for use in the preparation of clinical photoreceptor cell replacement therapies.