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1. Quantifying microbial energy supplies with the Water-Organic-Rock-Microbe (WORM) Portal (Oral Presentation)

   Boyer, Grayson; Weeks, Katelyn; Robare, Jordyn; Shock, Everett L (July 2025, Goldschmidt 2025 Conference)

   Microbes need energy to grow, reproduce, repair damage, maintain their metabolisms, and interact with their environment. Phototrophic microbes can harness the power of sunlight while chemotrophs derive energy from chemical compounds. Thermodynamic calculations can tell us whether a chemotrophic metabolic reaction will yield energy in an aqueous environment depending on fluid composition, temperature, and pressure. If the calculation reveals that energy is not available for a reaction, the reaction can be ruled out as a viable metabolic strategy in that system. Similarly, energy supplies can be quantified for energy-yielding reactions to generate hypotheses about how chemotrophic microbes harness energy in a system. Because of its usefulness for interpreting chemotroph metabolic strategies, several recent studies have quantified microbial energy supplies in natural systems and growth experiments using free and open-source software tools developed for the Water-Organic-Rock-Microbe (WORM) Portal online computing environment [1, 2, 3, 4]. The WORM Portal is an NSF-funded geochemical modeling platform for researchers, students, and the public that can be accessed for free through an internet browser. The WORM Portal comes pre-packaged with computational Jupyter notebook tools and educational demos covering a variety of topics in geobiology and geochemistry. In this presentation, we will demonstrate how the WORM Portal can be used to quantify microbial energy supplies, chemical affinities, and power (energy over time) in water samples and growth media under ambient conditions and elevated temperatures and pressures, and how you can apply the WORM Portal to quantify energy supplies in your own systems of interest. [1] Alain et al. (2022). Sulfur disproportionation is exergonic in the vicinity of marine hydrothermal vents. Environmental Microbiology, 24(5), 2210-2219. [2] Howells et al. (2025). Energetic and genomic potential for hydrogenotrophic, formatotrophic, and acetoclastic methanogenesis in surface-expressed serpentinized fluids of the Samail Ophiolite. Frontiers in Microbiology, 15, 1523912. [3] Parsons et al. "Hydrothermal Seepage of Altered Crustal Formation Water Seaward of the Middle America Trench, Offshore Costa Rica." Geochemistry, Geophysics, Geosystems 25.1 (2024): e2023GC011246. [4] Rhim et al. (2024). Mode of carbon and energy metabolism shifts lipid composition in the thermoacidophile Acidianus. Applied and Environmental Microbiology, 90(2), e01369-23. 

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2. Tidal Evolution and Diffusive Growth During High-eccentricity Planet Migration: Revisiting the Eccentricity Distribution of Hot Jupiters

   https://doi.org/10.3847/1538-4357/ac5627  

   Yu, Hang; Weinberg, Nevin N.; Arras, Phil (April 2022, The Astrophysical Journal)

   Abstract High-eccentricity tidal migration is a potential formation channel for hot Jupiters. During this process, the planetary f-mode may experience a phase of diffusive growth, allowing its energy to quickly build up to large values. In Yu et al., we demonstrated that nonlinear mode interactions between a parent f-mode and daughter f- and p-modes expand the parameter space over which the diffusive growth of the parent is triggered. We extend that study by incorporating (1) the angular momentum transfer between the orbit and the mode, and consequently the evolution of the pericenter distance; (2) a prescription to regulate the nonlinear frequency shift at high parent mode energies; and (3) dissipation of the parent’s energy due to both turbulent convective damping of the daughter modes and strongly nonlinear wave-breaking events. The new ingredients allow us to follow the coupled evolution of the mode and orbit over ≳10⁴yr, covering the diffusive evolution from its onset to its termination. We find that the semimajor axis shrinks by a factor of nearly 10 over 10⁴yr, corresponding to a tidal quality factor $\mathit{}\sim 10$. The f-mode’s diffusive growth terminates while the eccentricity is still high, at arounde= 0.8–0.95. Using these results, we revisit the eccentricity distribution of proto-hot Jupiters. We estimate that less than 1 proto-HJ with eccentricity >0.9 should be expected in Kepler's data once the diffusive regime is accounted for, explaining the observed paucity of this population. 

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3. Aerosol Measurements at Utqiagvik, Alaska, from 2022 to 2027 for Sustaining The Utqiagvik Aerosol Record of Decades (STUARD)

   https://doi.org/10.6075/J0W66KZF  

   Russell, Lynn M.; Saha, Sourita; Thomas, Bryan; Burgener, Ross; Andrews, Elizabeth; Thiemens, Mark H.; Quinn, Patricia; Upchurch, Lucia; Leaitch, W. Richard (February 2024, UC San Diego Library Digital Collections)

   Data availability pending. The Arctic is warming faster than any other place on Earth, with sea ice declining rapidly and sources of sea spray and biogenic aerosol emissions changing by consequence. Utqiagvik is at the forefront of this change, abutting one of the largest areas of sea ice loss. This change will have far-reaching impacts to both the environment and the community. Because this change has happened largely in the last decade, now is an important time to both document that change and to continue a data record that will allow for a characterization of the New Arctic, as climate is already altering the Arctic landscape forever. The longest and most complete record of aerosol properties in the American Arctic is that of Utqiagvik, making this unique location serve as a regional record of changes in atmospheric aerosol properties. This dataset will extend the baseline measurements of this Arctic aerosol record, including and continuing the 15-year record of submicron inorganic components (Quinn et al., 2009; Quinn et al., 2002), re-instituting the 2-year record of organic components collected a decade ago (Frossard et al., 2011; Shaw et al., 2010), enhancing the chemical analysis with sulfur isotopes to improve interpretation of emission sources (Kunasek et al., 2010; Thiemens & Lin, 2019), continuing particle number size distribution measurements (Freud et al., 2017), and re-starting cloud condensation nuclei measurements (Schmale, Henning, et al., 2018). 

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4. Assessing Replication of Pyrogenic Organic Compounds in Coeval Tropical Stalagmites

   Denniston, R.F.; Azenon, J.; Argiriadis, E.; Ondei, S.; Genuzio, G.; Baltieri, M.; Nguyen, H.; Thompson, J. (January 2022, Transactions American Geophysical Union)

   Polycyclic aromatic hydrocarbons (PAHs) are produced by the burning of biomass, with molecular weights reflecting combustion conditions. After being formed, PAHs are transported downward through soil and bedrock by infiltrating rainwater (Perrette et al., 2013), and in karst areas can become incorporated into stalagmites as they crystallize from dripwater in underlying caves (Perrette et al., 2008; Denniston et al., 2018). Thus, when stalagmite growth is high, infiltration times short, and fluid mixing minimized, there exists the potential for PAHs in stalagmites to preserve evidence of the presence and intensity of fire through time. We have previously reported a high-resolution analysis of PAH distributions in two non-overlapping aragonite stalagmites from cave KNI-51, tropical Western Australia, that together span the majority of the last 900 years. The geologic conditions of this site make it well suited for the transmission of discrete pulses of fire-derived compounds from the land surface to the stalagmite. Soils are thin to absent above the stalagmite chamber and the cave is shallow. As a result, homogenization of infiltrated water (and thus PAHs) is expected to be small on interannual time scales. In addition, intense summer monsoon rains flush fire debris from the hillsides over the cave. These characteristics, coupled with the fast growth rates (1-2 mm/yr) and precise radiometric dates (±1-30 years 2 s.d. over the last millennium) of KNI-51 stalagmites suggest that they hold the potential for extremely high resolution paleofire reconstruction. Here we provide the first test of replication of PAH abundances, ratios, and trends in coeval stalagmites. Samples were analyzed at Ca’ Foscari University using methods of Argiriadis et al. (2019) and the results validated by comparing them with fire activity detected through satellite images. Stalagmites KNI-51-F and -G overlap in age from CE 1310-1630, allowing an examination of the consistency of the PAH signal along different infiltration pathways. References Argiriadis, E. et al. (2019) European Geosciences Union Annual Meeting, Vienna, Australia. Denniston, R.F. et al. (2018) American Geophysical Union Annual Meeting, Washington, D.C. Perrette, Y. et al. (2008) Chemical Geology, 251, 67-76. Perrette, Y. et al. (2013) Organic Geochemistry, 65, 37-45. 

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5. Aerosol Measurements at Utqiagvik, Alaska, from 2022 to 2027 for Sustaining The Utqiagvik Aerosol Record of Decades (STUARD)

   https://doi.org/10.18739/A2X05XF2D  

   Russell, Lynn; Saha, Sourita; Thomas, Bryan; Burgener, Ross; Andrews, Elizabeth; Thiemens, Mark; Quinn, Patricia; Upchurch, Lucia; Leaitch, Richard (January 2024, NSF Arctic Data Center)

   ### Access Dataset and extensive metadata can be accessed and downloaded from the 'ADC' directory via: [http://arcticdata.io/data/10.18739/A2X05XF2D](http://arcticdata.io/data/10.18739/A2X05XF2D) ### Overview The Arctic is warming faster than any other place on Earth, with sea ice declining rapidly and sources of sea spray and biogenic aerosol emissions changing by consequence. Utqiagvik is at the forefront of this change, abutting one of the largest areas of sea ice loss. This change will have far-reaching impacts to both the environment and the community. Because this change has happened largely in the last decade, now is an important time to both document that change and to continue a data record that will allow for a characterization of the New Arctic, as climate is already altering the Arctic landscape forever. The longest and most complete record of aerosol properties in the American Arctic is that of Utqiagvik, making this unique location serve as a regional record of changes in atmospheric aerosol properties. This dataset will extend the baseline measurements of this Arctic aerosol record, including and continuing the 15-year record of submicron inorganic components (Quinn et al., 2009; Quinn et al., 2002), re-instituting the 2-year record of organic components collected a decade ago (Frossard et al., 2011; Shaw et al., 2010), enhancing the chemical analysis with sulfur isotopes to improve interpretation of emission sources (Kunasek et al., 2010; Thiemens & Lin, 2019), continuing particle number size distribution measurements (Freud et al., 2017), and re-starting cloud condensation nuclei measurements (Schmale, Henning, et al., 2018). 

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