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Marine macroalgae in the Gulf of Mexico is an important potential source for biofuel. However, identifying locations with the correct biogeochemical and hydrodynamic conditions for cultivation on a large enough scale to meet the needs of the U.S. private energy sector is impossible from purely observational studies. Large-scale, HPC modeling of earth systems processes enables researchers to study complex physical relationships with high fidelity. Here, we present novel visualization techniques showing the results of a global run of the E3SM’s MPAS-Ocean model data with biogeochemistry extensions to improve ongoing research in macroalgae cultivation. 

Abstract Stars that interact with supermassive black holes (SMBHs) can be either completely or partially destroyed by tides. In a partial tidal disruption event (TDE), the high-density core of the star remains intact, and the low-density outer envelope of the star is stripped and feeds a luminous accretion episode. The TDE AT 2018fyk, with an inferred black hole mass of 10^7.7±0.4M_⊙, experienced an extreme dimming event at X-ray (factor of >6000) and UV (factor of ∼15) wavelengths ∼500–600 days after discovery. Here we report on the reemergence of these emission components roughly 1200 days after discovery. We find that the source properties are similar to those of the predimming accretion state, suggesting that the accretion flow was rejuvenated to a similar state. We propose that a repeated partial TDE, where the partially disrupted star is on an ∼1200 day orbit about the SMBH and periodically stripped of mass during each pericenter passage, powers its unique light curve. This scenario provides a plausible explanation for AT 2018fyk’s overall properties, including the rapid dimming event and the rebrightening at late times. We also provide testable predictions for the behavior of the accretion flow in the future; if the second encounter was also a partial disruption, then we predict another strong dimming event around day 1800 (2023 August) and a subsequent rebrightening around day 2400 (2025 March). This source provides strong evidence of the partial disruption of a star by an SMBH. 

Chinese Dynamic penetration test (DPT) is an in-situ testing with the advantages of simple apparatus, economical test, and continuous data acquisition, especially for measuring bearing capacity, relative density and classification of gravelly soils. The typical gravelly soils sites are selected from the Chengdu Plain in China and the river bed of Echo dam downstream in the U.S., and China-US dynamic penetration testing and hammer energy measurements are conducted. The results show that: (1) The average of energy transfer ratios is 90% and the standard deviation is 7.7%, derived from 1321 energy time-history records, tested at 3 gravelly soils sites in the Chengdu Plain. The deviation is greatly affected by operation procedure. (2) The DPT test depth, using US drill rig assembling with Chinese DPT cone, can reach as much as 20 meters for assessing soil properties. (3) The average of energy transfer ratios is around 74% and the standard deviation is 8.7%, derived from 1438 energy time-history records, tested at 2 gravelly soils sites on the river bed of Echo dam downstream. The deviation is greatly affected by friction of drill rod and rope. (4) The DPT blows should be corrected according to different hammer energies. The proposed evaluation method for gravelly soils liquefaction, developed from the DPT database of gravelly soils liquefied during 2008 Wenchuan Earthquake, can be applicable for worldwide use. 

Abstract We present results from a search for X-ray/gamma-ray counterparts of gravitational-wave (GW) candidates from the third observing run (O3) of the LIGO–Virgo–KAGRA network using the Swift Burst Alert Telescope (Swift-BAT). The search includes 636 GW candidates received with low latency, 86 of which have been confirmed by the offline analysis and included in the third cumulative Gravitational-Wave Transient Catalogs (GWTC-3). Targeted searches were carried out on the entire GW sample using the maximum-likelihood Non-imaging Transient Reconstruction and Temporal Search pipeline on the BAT data made available via the GUANO infrastructure. We do not detect any significant electromagnetic emission that is temporally and spatially coincident with any of the GW candidates. We report flux upper limits in the 15–350 keV band as a function of sky position for all the catalog candidates. For GW candidates where the Swift-BAT false alarm rate is less than 10⁻³Hz, we compute the GW–BAT joint false alarm rate. Finally, the derived Swift-BAT upper limits are used to infer constraints on the putative electromagnetic emission associated with binary black hole mergers. 

Abstract Despite the growing number of binary black hole coalescences confidently observed through gravitational waves so far, the astrophysical origin of these binaries remains uncertain. Orbital eccentricity is one of the clearest tracers of binary formation channels. Identifying binary eccentricity, however, remains challenging due to the limited availability of gravitational waveforms that include the effects of eccentricity. Here, we present observational results for a waveform-independent search sensitive to eccentric black hole coalescences, covering the third observing run (O3) of the LIGO and Virgo detectors. We identified no new high-significance candidates beyond those that have already been identified with searches focusing on quasi-circular binaries. We determine the sensitivity of our search to high-mass (total source-frame massM> 70M_⊙) binaries covering eccentricities up to 0.3 at 15 Hz emitted gravitational-wave frequency, and use this to compare model predictions to search results. Assuming all detections are indeed quasi-circular, for our fiducial population model, we place a conservative upper limit for the merger rate density of high-mass binaries with eccentricities 0 <e≤ 0.3 at 16.9 Gpc⁻³yr⁻¹at the 90% confidence level.