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Traditional single-fiber spectroscopy provides a single galaxy spectrum, forming the basis for crucial parameter estimation. However, its accuracy can be compromised by various sources of contamination, such as the prominent H α emission line originating from both star-forming (SF) regions and non-star-forming (NonSF) regions, including active galactic nuclei. The potential to dissect a spectrum into its SF and NonSF constituents holds the promise of significantly enhancing precision in parameter estimates. In contrast, integral field unit (IFU) surveys present a solution to minimize contamination. These surveys examine spatially localized regions within galaxies, reducing the impact of mixed sources. Although an IFU survey’s resulting spectrum covers a smaller region of a galaxy than single-fiber spectroscopy, it can still encompass a blend of heterogeneous sources. Our study introduces an innovative model informed by insights from the Mapping Nearby Galaxies at Apache Point Observatory IFU survey. This model enables the decomposition of galaxy spectra, including those from the Sloan Digital Sky Survey, into SF and NonSF components. Applying our model to these survey data sets produces two distinct spectra, one for SF and another for NonSF components, while conserving flux across wavelength bins. When these decomposed spectra are visualized on a Baldwin, Phillips, and Terlevich (BPT) diagram, interesting patterns emerge. There is a significant shift in the placement of the NonSF decomposed spectra, as well as the emergence of two distinct clusters in the Low-ionization Nuclear Emission-line Region and the Seyfert region. This shift highlights the key role of SF “contamination” in influencing the positioning of NonSF spectra within the BPT diagram.

We present a novel approach for identifying cosmic web filaments within the DisPerSE structure identification framework, using cosmic density field estimates from the Monte Carlo Physarum Machine (MCPM), inspired by the slime mold organism. We apply our method to the IllustrisTNG (TNG100) cosmological simulations and investigate the impact of filaments on galaxies. The MCPM density field is superior to the Delaunay tessellation field estimator in tracing the true underlying matter distribution and allows filaments to be identified with higher fidelity, finding more low-prominence/diffuse filaments. Using our new filament catalogs, we find that ≳90% of galaxies are located within ∼1.5 Mpc of a filamentary spine, with little change in the median star formation activity with distance to the nearest filament. Instead, we uncover a differential effect of the local filament line density, Σ _fil (MCPM)—the total MCPM overdensity per unit length along a filament segment—on galaxy formation: most galaxies are quenched and gas-poor near high-line density filaments at z ≤ 1. At earlier times, the filamentary environment appears to have no effect on galactic gas supply and quenching. At z = 0, quenching in $\mathrm{log}({M}_{* }/{M}_{\odot })\gtrsim 10.5$ galaxies is mainly driven by mass, while lower-mass galaxies are significantly affected by the filament line density. Satellites are far more susceptible to filaments than centrals. The local environments of massive halos are not sufficient to account for the effect of filament line density on gas removal and quenching. Our new approach holds great promise for observationally identifying filaments from galaxy surveys such as SDSS and DESI.

Despite the importance of feedback from active galactic nuclei (AGNs) in models of galaxy evolution, observational constraints on the influence of AGN feedback on star formation remain weak. To this end, we have compared the star formation trends of 279 low-redshift AGN galaxies with 558 inactive control galaxies using integral field unit spectroscopy from the Sloan Digital Sky Survey-IV Mapping Nearby Galaxies at Apache Point Observatory survey. With a Gaussian-process-based methodology, we reconstruct nonparametric star formation histories in spatially resolved spaxels covering the face of each galaxy. Based on the galaxy-wide star formation rates (SFRs) alone, we find no obvious signatures of AGN feedback. However, the AGN galaxies have significantly suppressed central (kiloparsec-scale) SFRs, lying up to a factor of 2 below those of the control galaxies, providing direct observational evidence of AGN feedback suppressing star formation. The suppression of central SFRs in the AGN galaxies began in the central regions ∼6 Gyr ago (redshift z ∼ 0.7), taking place over a few gigayears. A small subset of the AGN galaxies were rapidly driven to quiescence shortly before being observed (in the last 500 Myr), potentially indicating instances of AGN-driven feedback. More frequently, however, star formation continues in the AGN galaxies, with suppression primarily in the central regions. This is suggestive of a picture in which integrated (gigayear-timescale) AGN feedback can significantly affect central star formation, but may be inefficient in driving galaxy-wide quenching in low-redshift galaxies, instead leaving them in the green valley.

Bronchomotor tone modulated by airway smooth muscle shortening represents a key mechanism that increases airway resistance in asthma. Altered glucose metabolism in inflammatory and airway structural cells is associated with asthma. Although these observations suggest a causal link between glucose metabolism and airway hyperresponsiveness, the mechanisms are unclear. We hypothesized that glycolysis modulates excitation–contraction coupling in human airway smooth muscle (HASM) cells. Cultured HASM cells from human lung donors were subject to metabolic screenings using Seahorse XF cell assay. HASM cell monolayers were treated with vehicle or PFK15 (1-(Pyridin-4-yl)-3-(quinolin-2-yl)prop-2-en-1-one), an inhibitor of PFKFB3 (PFK-1,6-phosphofructo-2-kinase/fructose-2,6- biphosphatase 3) that generates an allosteric activator for glycolysis rate-limiting enzyme PFK1 (phosphofructokinase 1), for 5–240 minutes, and baseline and agonist-induced phosphorylation of MLC (myosin light chain), MYPT1 (myosin phosphatase regulatory subunit 1), Akt, RhoA, and cytosolic Ca2+ were determined. PFK15 effects on metabolic activity and contractile agonist–induced bronchoconstriction were determined in human precision-cut lung slices. Inhibition of glycolysis attenuated carbachol-induced excitation–contraction coupling in HASM cells. ATP production and bronchodilator-induced cAMP concentrations were also attenuated by glycolysis inhibition in HASM cells. In human small airways, glycolysis inhibition decreased mitochondrial respiration and ATP production and attenuated carbachol-induced bronchoconstriction. The findings suggest that energy depletion resulting from glycolysis inhibition is a novel strategy for ameliorating HASM cell shortening and bronchoprotection of human small airways. [ABSTRACT FROM AUTHOR]