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Normal routine electroencephalograms (EEGs) can cause delays in the diagnosis and treatment of epilepsy, especially in drug-resistant patients and those without structural abnormalities. There is a need for alternative quantitative approaches that can inform clinical decisions when traditional visual EEG review is inconclusive. We leverage a large population EEG database (N = 13,652 recordings, 12,134 unique patients) and an independent cohort of patients with focal epilepsy (N = 121) to investigate whether normal EEG segments could support the diagnosis of focal epilepsy. We decomposed expertly graded normal EEGs (N = 6,242) using unsupervised tensor decomposition to extract the dominant spatio-spectral patterns present in a clinical population. We then, using the independent cohort of patients with focal epilepsy, evaluated whether pattern loadings of normal interictal EEG segments could classify focal epilepsy, the epileptogenic lobe, presence of lesions, and drug response. We obtained six physiological patterns of EEG spectral power and connectivity with distinct spatio-spectral signatures. Both pattern types together effectively differentiated patients with focal epilepsy from non-epileptic controls (mean AUC 0.78) but failed to classify the epileptogenic lobe. Spectral power-based patterns best classified drug-resistant epilepsy (mean AUC 0.73) and lesional epilepsy (mean AUC 0.67), albeit with high variability across patients. Our findings support that visibly normal patient EEGs contain subtle quantitative differences of clinical relevance. Further development may yield normal EEG-based computational biomarkers that can augment traditional EEG review and epilepsy care. 

Abstract We presentFrankenBlast, a customized and improved version of theBlastweb application.FrankenBlastassociates transients to their host galaxies, performs host photometry, and runs a innovative spectral energy distribution fitting code to constrain host stellar population properties—all within minutes per object. We testFrankenBlaston 14,432 supernovae (SNe), ≈half of which are spectroscopically classified, and are able to constrain host properties for 9262 events. When contrasting the host stellar masses (M_*), specific star formation rates (sSFR), and host dust extinction (A_V) between spectroscopically and photometrically classified SNe Ia, Ib/c, II, and IIn, we determine that deviations in these distributions are primarily due to misclassified events contaminating the photometrically classified sample. We further show that the higher redshifts of the photometrically classified sample also force theirM_*and sSFR distributions to deviate from those of the spectroscopically classified sample, as these properties are redshift-dependent. We compare host properties between spectroscopically classified SN populations and determine if they primarily traceM_*or SFR. We find that all SN populations seem to both depend onM_*and SFR, with SNe II and IIn somewhat more SFR-dependent than SNe Ia and Ib/c, and SNe Ia moreM_*-dependent than all other classes. We find the difference in the SNe Ib/c and II hosts to be the most intriguing and speculate that SNe Ib/c must be more dependent on higherM_*and more evolved environments for the right conditions for progenitor formation. All data products andFrankenBlastare publicly available, along with a developingFrankenBlastversion intended for Rubin Observatory science products. 

Abstract As a mechanism of the dilution effect, predation and filter feeding on parasitic propagules are hypothesized to reduce transmission to susceptible hosts and alter host–parasite interactions. In marine systems, the effect of other community members on the disease dynamics of microparasites in their suitable hosts is poorly known. In a coastal estuarine host–parasite system, we examined how eastern oysters,Crassostrea virginica, affect the transmission of a parasitic dinoflagellate,Hematodinium perezi, to juvenile blue crabs,Callinectes sapidus. We deployed juvenile blue crabs in custom mesh bags that were sandwiched by oysters into holo‐endemic areas, or areas with high endemic transmission for the parasite in juvenile hosts. Controls consisted of juvenile crabs deployed with an equivalent number of oyster shells to test for the effect of rugosity on transmission and crabs deployed alone. Deployments lasted 7–13 days and were done over different temporal and spatial scales. Results from the field deployments suggest that oysters, not shells, reduced the probability of infection to crab hosts. To investigate consumption in the laboratory, single oysters in 1 L aquaria were fed dinospores ofH. perezireleased from infected crabs. Oysters reduced parasite densities in the water at rates similar to those observed for a common phytoplankton,Tetraselmis chui, that is grown specifically as oyster food. Our results jointly support that oysters benefit adjacent community members through feeding on transmissive stages of their pathogens and highlight the need for additional field‐based approaches addressing environmental heterogeneity in pathogen transmission. 

Abstract We conduct an analysis of over 60,000 dwarf galaxies ( $7\lesssim \log M_{*}/M_{\odot }\lesssim 10$) in search of photometric variability indicative of active galactic nuclei (AGNs). Using data from the Young Supernova Experiment, a time domain survey on the Pan-STARRS telescopes, we construct light curves for each galaxy in up to four bands (griz) where available. We select objects with AGN-like variability by fitting each light curve with a damped random walk (DRW) model. After quality cuts and removing transient contaminants, we identify 1100 variability-selected AGN candidates (representing 2.4% of the available sample). We analyze their spectra to measure various emission lines and calculate black hole (BH) masses, finding general agreement with previously found mass scaling relations and nine potential intermediate-mass BH candidates. Furthermore, we reanalyze the light curves of our candidates to calculate the dampening timescaleτ_DRWassociated with the DRW and see a similar correlation between this value and the BH mass. Finally, we estimate the active fraction as a function of stellar mass and see evidence that the active fraction increases with host mass. 

Abstract At the low-redshift end (z< 0.05) of the Hubble diagram with Type Ia Supernovae (SNe Ia), the contribution to Hubble residual scatter from peculiar velocities (PVs) is of similar size to that due to the limitations of the standardization of the SN Ia light curves. A way to improve the redshift measurement of the SN host galaxy is to utilize the average redshift of the galaxy group, effectively averaging over small-scale/intracluster PVs. One limiting factor is the fraction of SN host galaxies in galaxy groups, previously found to be 30% using (relatively incomplete) magnitude-limited galaxy catalogs. Here, we do the first analysis ofN-body simulations to predict this fraction, finding ∼73% should have associated groups and group averaging should improve redshift precision by ∼135 km s⁻¹(∼0.04 mag atz= 0.025). Furthermore, using spectroscopic data from the Anglo-Australian Telescope, we present results from the first pilot program to evaluate whether or not 23 previously unassociated SN Ia hosts belong in groups. We find that 91% of these candidates can be associated with groups, consistent with predictions from simulations given the sample size. Combining with previously assigned SN host galaxies in Pantheon+, we demonstrate improvement in Hubble residual scatter equivalent to 145 km s⁻¹, also consistent with simulations. For new and upcoming low-zsamples from, for example, the Zwicky Transient Facility and the Legacy Survey of Space and Time, a separate follow-up program identifying galaxy groups of SN hosts is a highly cost-effective way to enhance their constraining power. 

Abstract The Dark Energy Spectroscopic Instrument (DESI) collaboration measured a tight relation between the Hubble constant (H₀) and the distance to the Coma cluster using the fundamental plane (FP) relation of the deepest, most homogeneous sample of early-type galaxies. To determineH₀, we measure the distance to Coma by several independent routes, each with its own geometric reference. We measure the most precise distance to Coma from 13 Type Ia supernovae (SNe Ia) in the cluster with a mean standardized brightness of $m_B^0=15.710\pm 0.040$mag. Calibrating the absolute magnitude of SNe Ia with the Hubble Space Telescope (HST) distance ladder yieldsD_Coma = 98.5 ± 2.2 Mpc, consistent with its canonical value of 95–100 Mpc. This distance results inH₀ = 76.5 ± 2.2 km s⁻¹Mpc⁻¹from the DESI FP relation. Inverting the DESI relation by calibrating it instead to the Planck+ΛCDM value ofH₀ = 67.4 km s⁻¹Mpc⁻¹implies a much greater distance to Coma,D_Coma = 111.8 ± 1.8 Mpc, 4.6σbeyond a joint, direct measure. Independent of SNe Ia, the HST Key Project FP relation as calibrated by Cepheids, the tip of the red giant branch from JWST, or HST near-infrared surface brightness fluctuations all yieldD_Coma < 100 Mpc, in joint tension themselves with the Planck-calibrated route at >3σ. From a broad array of distance estimates compiled back to 1990, it is hard to see how Coma could be located as far as the Planck+ΛCDM expectation of >110 Mpc. By extending the Hubble diagram to Coma, a well-studied location in our own backyard whose distance was in good accord well before the Hubble tension, DESI indicates a more pervasive conflict between our knowledge of local distances and cosmological expectations. We expect future programs to refine the distance to Coma and nearer clusters to help illuminate this new local window on the Hubble tension. 

Abstract Luminous interacting supernovae (SNe) are a class of stellar explosions whose progenitors underwent vigorous mass loss in the years prior to core collapse. While the mechanism by which this material is ejected is still debated, obtaining the full density profile of the circumstellar medium (CSM) could reveal more about this process. Here, we present an extensive multiwavelength study of PS1-11aop, a luminous and slowly declining Type IIn SNe discovered by the Pan-STARRS Medium Deep Survey. PS1-11aop had a peakr-band magnitude of −20.5 mag, a total radiated energy >8 × 10⁵⁰erg, and it exploded near the center of a star-forming galaxy with super-solar metallicity. We obtained multiple detections at the location of PS1-11aop in the radio and X-ray bands between 4 and 10 yr post-explosion, and if due to the supernova (SN), it is one of the most luminous radio SNe identified to date. Taken together, the multiwavelength properties of PS1-11aop are consistent with a CSM density profile with multiple zones. The early optical emission is consistent with the SN blastwave interacting with a dense and confined CSM shell, which contains multiple solar masses of material that was likely ejected in the final <10–100 yr prior to the explosion, (∼0.05−1.0M_⊙yr⁻¹at radii of ≲10¹⁶cm). The radio observations, on the other hand, are consistent with a sparser environment (≲2 × 10⁻³M_⊙yr⁻¹at radii of ∼0.5–1 × 10¹⁷cm)—thus probing the history of the progenitor star prior to its final mass-loss episode. 

Abstract We present a detailed analysis of AT 2020nov, a tidal disruption event (TDE) in the center of its host galaxy, located at a redshift ofz= 0.083. AT 2020nov exhibits unique features, including double-peaked Balmer emission lines, a broad UV/optical flare, and a peak log luminosity in the extreme-ultraviolet (EUV) estimated at $\sim 45.66_{-0.33}^{+0.10}\mathrm{erg}{\mathrm{s}}^{-1}$. A late-time X-ray flare was also observed, reaching an absorbed luminosity of 1.67 × 10⁴³erg s⁻¹approximately 300 days after the UV/optical peak. Multiwavelength coverage, spanning optical, UV, X-ray, and mid-infrared (MIR) bands, reveals a complex spectral energy distribution (SED) that includes MIR flaring indicative of dust echoes, suggesting a dust covering fraction consistent with typical TDEs. Spectral modeling indicates the presence of an extended, quiescent disk around the central supermassive black hole with a radius of $\sim 5.06_{-0.77}^{+0.59}\times 10^4{R}_{\mathrm{g}}$. The multicomponent SED model, which includes a significant EUV component, suggests that the primary emission from the TDE is reprocessed by this extended disk, producing the observed optical and MIR features. The lack of strong active galactic nuclei signatures in the host galaxy, combined with the quiescent disk structure, highlights AT 2020nov as a rare example of a TDE occurring in a galaxy with a dormant but extended preexisting accretion structure. 

ABSTRACT We introduce the Hawai‘i Supernova Flows project and present summary statistics of the first 1217 astronomical transients observed, 668 of which are spectroscopically classified Type Ia Supernovae (SNe Ia). Our project is designed to obtain systematics-limited distances to SNe Ia while consuming minimal dedicated observational resources. To date, we have performed almost 5000 near-infrared (NIR) observations of astronomical transients and have obtained spectra for over 200 host galaxies lacking published spectroscopic redshifts. In this survey paper, we describe the methodology used to select targets, collect/reduce data, calculate distances, and perform quality cuts. We compare our methods to those used in similar studies, finding general agreement or mild improvement. Our summary statistics include various parametrizations of dispersion in the Hubble diagrams produced using fits to several commonly used SN Ia models. We find the lowest dispersions using the SNooPy package’s EBV_model2, with a root mean square deviation of 0.165 mag and a normalized median absolute deviation of 0.123 mag. The full utility of the Hawai‘i Supernova Flows data set far exceeds the analyses presented in this paper. Our photometry will provide a valuable test bed for models of SN Ia incorporating NIR data. Differential cosmological studies comparing optical samples and combined optical and NIR samples will have increased leverage for constraining chromatic effects like dust extinction. We invite the community to explore our data by making the light curves, fits, and host galaxy redshifts publicly accessible.