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We report the discovery of 11 high-velocity H I clouds at Galactic latitudes of 25°–30°, likely embedded in the Milky Way’s nuclear wind. The clouds are detected with deep Green Bank Telescope 21 cm observations of a 3.2° × 6.2° field around QSO 1H1613-097, located behind the northern Fermi Bubble. Our measurements reach 3sigma limits on NHI as low as 3.1 × 10^17/cm^2, more than twice as sensitive as previous HI studies of the bubbles. The clouds span −180 ≤v_LSR≤ −90 km/s and are the highest-latitude 21 cm high-velocity cloud detected inside the bubbles. Eight clouds are spatially resolved, showing coherent structures with sizes of 4–28 pc, peak column densities of log HI = 17.9–18.7, and HI masses up to 1470M⊙. Several exhibit internal velocity gradients. Their presence at such high latitudes is surprising, given the short expected survival times for clouds expelled from the Galactic center. These objects may be fragments of a larger cloud disrupted by interaction with the surrounding hot gas. 

Abstract As part of the Deciphering the Interplay between the Interstellar medium, Stars, and the Circumgalactic medium (DIISC) survey, we present the UV metal absorption features in the circumgalactic medium (CGM) near the Higas disk (<4.5R_HI) of 31 nearby galaxies through quasar absorption-line spectroscopy. Of the ions under study, Siiiiλ1206 was most frequently detected (18 of 31 sight lines), while Ciiλ1334 and Siiiλ1260 were detected in 17 and 15 of 31 sight lines, respectively. Many components were consistent with photoionization equilibrium models; most of the cold and cool gas phase clouds were found to have lengths smaller than 2 kpc. Sight lines with smaller impact parameters (ρ) normalized by the galaxy’s virial radius (R_vir) and Hiradius (R_HI) tend to have more components and larger rest-frame equivalent widths (W_r) than those that probe the CGM at larger radii. In particular, we find that the location of metals are better traced byρ/R_HIrather than the traditionalρ/R_vir. Larger covering fractions are found closer to galaxies, with a radial decline that depends on theW_rlimit used. Our results provide new insights into the spatial distribution of metals around the Hidisks of low-redshift galaxies. 

The research objective is to estimate consumer willingness to pay (WTP) for electricity grid fortification. Data are from a representative survey of Oklahoma citizens. Extreme weather events, aging utility infrastructure, increased demand for affordable energy, and terrorism threaten the safety and security of the way most citizens access electricity. This study is a first look at public willingness to support energy grid security measures in the United States Southern Great Plains. Findings suggest that consumers would pay an additional 14.69 in monthly utility bills for a fortified grid. This WTP estimate is close to a recent energy bill hike of 14 initiated by local electricity providers. The findings provide policymakers and energy providers with information on consumer willingness to support efforts to modernize the current grid. 

Abstract Specifically selected to leverage the unique ultraviolet capabilities of the Hubble Space Telescope, the Hubble Ultraviolet Legacy Library of Young Stars as Essential Standards (ULLYSES) is a Director’s Discretionary program of approximately 1000 orbits—the largest ever executed—that produced a UV spectroscopic library of O and B stars in nearby low-metallicity galaxies and accreting low-mass stars in the Milky Way. Observations from ULLYSES combined with archival spectra uniformly sample the fundamental astrophysical parameter space for each mass regime, including spectral type, luminosity class, and metallicity for massive stars, and the mass, age, and disk accretion rate for low-mass stars. The ULLYSES spectral library of massive stars will be critical to characterize how massive stars evolve at different metallicities; to advance our understanding of the production of ionizing photons, and thus of galaxy evolution and the re-ionization of the Universe; and to provide the templates necessary for the synthesis of integrated stellar populations. The massive-star spectra are also transforming our understanding of the interstellar and circumgalactic media of low-metallicity galaxies. On the low-mass end, UV spectra of T Tauri stars contain a plethora of diagnostics of accretion, winds, and the warm disk surface. These diagnostics are crucial for evaluating disk evolution and provide important input to assess atmospheric escape of planets and to interpret powerful probes of disk chemistry, as observed with the Atacama Large Millimeter Array and the James Webb Space Telescope. In this paper, we motivate the design of the program, describe the observing strategy and target selection, and present initial results. 

Abstract We explore the growth of the stellar disks in 14 nearby spiral galaxies as part of the Deciphering the Interplay between the Interstellar medium, Stars, and the Circumgalactic medium (DIISC) survey. We study the radial distribution of specific star formation rates (sSFRs) and investigate the ratio of the difference in the outer and inner sSFRs (Δ_sSFR= sSFR_out– sSFR_in) of the disk and the total sSFR, Δ_sSFR/sSFR, to quantify disk growth. We find Δ_sSFR/sSFR and the Higas fraction to show a mild correlation of Spearman’sρ= 0.30, indicating that star formation and disk growth are likely to proceed outward in galactic disks with high Higas fractions. The Higas fractions and Δ_sSFR/sSFR of the galaxies also increase with the distance to the nearestL_⋆neighbor, suggesting that galaxies are likely to sustain the cold gas in their interstellar medium and exhibit inside-out growth in isolated environments. However, the Hicontent in their circumgalactic medium (CGM), probed by the Lyαequivalent width (W_Lyα) excess, is observed to be suppressed in isolated environments, as is apparent from the strong anticorrelation between theW_Lyαexcess and the distance to the fifth nearestL_⋆neighbor (Spearman’sρ= −0.62). As expected,W_Lyαis also found to be suppressed in cluster galaxies. We find no relation between theW_Lyαexcess of the detected CGM absorber and Δ_sSFR/sSFR, implying that the enhancement and suppression of the circumgalactic Higas does not affect the direction in which star formation proceeds in a galactic disk or vice versa. 

Anxiety disorders are a major public health concern and current treatments are inadequate for many individuals. Anxiety is more common in women than men and this difference arises during puberty. Sex differences in physiological stress responses may contribute to this variability. During puberty, gonadal hormones shape brain structure and function, but the extent to which these changes affect stress sensitivity is unknown. We examined how pubertal androgens shape behavioral and neural responses to social stress in California mice (Peromyscus californicus), a model species for studying sex differences in stress responses. In adults, social defeat reduces social approach and increases social vigilance in females but not males. We show this sex difference is absent in juveniles, and that prepubertal castration sensitizes adult males to social defeat. Adult gonadectomy does not alter behavioral responses to defeat, indicating that gonadal hormones act during puberty to program behavioral responses to stress in adulthood. Calcium imaging in the medioventral bed nucleus of the stria terminalis (BNST) showed that social threats increased neural activity and that prepubertal castration generalized these responses to less threatening social contexts. These results support recent hypotheses that the BNST responds to immediate threats. Prepubertal treatment with the nonaromatizable androgen dihydrotestosterone acts in males and females to reduce the effects of defeat on social approach and vigilance in adults. These data indicate that activation of androgen receptors during puberty is critical for programming behavioral responses to stress in adulthood. 

Light pollution is a global threat to biodiversity, especially migratory organisms, some of which traverse hemispheric scales. Research on light pollution has grown significantly over the past decades, but our review of migratory organisms demonstrates gaps in our understanding, particularly beyond migratory birds. Research across spatial scales reveals the multifaceted effects of artificial light on migratory species, ranging from local and regional to macroscale impacts. These threats extend beyond species that are active at night – broadening the scope of this threat. Emerging tools for measuring light pollution and its impacts, as well as ecological forecasting techniques, present new pathways for conservation, including transdisciplinary approaches. 

Abstract The Large Magellanic Cloud (LMC) and the Small Magellanic Cloud (SMC) are the closest massive satellite galaxies of the Milky Way. They are probably on their first passage on an infalling orbit towards our Galaxy 1 and trace the continuing dynamics of the Local Group 2 . Recent measurements of a high mass for the LMC ( M halo  ≈ 10 11.1–11.4   M ⊙ ) 3–6 imply that the LMC should host a Magellanic Corona: a collisionally ionized, warm-hot gaseous halo at the virial temperature (10 5.3–5.5  K) initially extending out to the virial radius (100–130 kiloparsecs (kpc)). Such a corona would have shaped the formation of the Magellanic Stream 7 , a tidal gas structure extending over 200° across the sky 2,8,9 that is bringing in metal-poor gas to the Milky Way 10 . Here we show evidence for this Magellanic Corona with a potential direct detection in highly ionized oxygen (O +5 ) and indirectly by means of triply ionized carbon and silicon, seen in ultraviolet (UV) absorption towards background quasars. We find that the Magellanic Corona is part of a pervasive multiphase Magellanic circumgalactic medium (CGM) seen in many ionization states with a declining projected radial profile out to at least 35 kpc from the LMC and a total ionized CGM mass of log 10 ( M H II,CGM / M ⊙ ) ≈ 9.1 ± 0.2. The evidence for the Magellanic Corona is a crucial step forward in characterizing the Magellanic group and its nested evolution with the Local Group. 

Abstract Delivering genes to and across the brain vasculature efficiently and specifically across species remains a critical challenge for addressing neurological diseases. We have evolved adeno-associated virus (AAV9) capsids into vectors that transduce brain endothelial cells specifically and efficiently following systemic administration in wild-type mice with diverse genetic backgrounds, and in rats. These AAVs also exhibit superior transduction of the CNS across non-human primates (marmosets and rhesus macaques), and in ex vivo human brain slices, although the endothelial tropism is not conserved across species. The capsid modifications translate from AAV9 to other serotypes such as AAV1 and AAV-DJ, enabling serotype switching for sequential AAV administration in mice. We demonstrate that the endothelial-specific mouse capsids can be used to genetically engineer the blood-brain barrier by transforming the mouse brain vasculature into a functional biofactory. We apply this approach to Hevin knockout mice, where AAV-X1-mediated ectopic expression of the synaptogenic protein Sparcl1/Hevin in brain endothelial cells rescued synaptic deficits. 

ABSTRACT The flow of gas into and out of galaxies leaves traces in the circumgalactic medium which can then be studied using absorption lines towards background quasars. We analyse 27 $${{\log [N({\textrm {H}}\, {\small {I}})/\rm {cm}^{-2}]}} > 18.0$$ H i absorbers at z = 0.2 to 1.4 from the MUSE-ALMA Haloes survey with at least one galaxy counterpart within a line of sight velocity of ±500 km s−1. We perform 3D kinematic forward modelling of these associated galaxies to examine the flow of dense, neutral gas in the circumgalactic medium. From the VLT/MUSE, HST broad-band imaging, and VLT/UVES and Keck/HIRES high-resolution UV quasar spectroscopy observations, we compare the impact parameters, star-formation rates, and stellar masses of the associated galaxies with the absorber properties. We find marginal evidence for a bimodal distribution in azimuthal angles for strong H i absorbers, similar to previous studies of the Mg ii and O vi absorption lines. There is no clear metallicity dependence on azimuthal angle, and we suggest a larger sample of absorbers is required to fully test the relationship predicted by cosmological hydrodynamical simulations. A case-by-case study of the absorbers reveals that ten per cent of absorbers are consistent with gas accretion, up to 30 per cent trace outflows, and the remainder trace gas in the galaxy disc, the intragroup medium, and low-mass galaxies below the MUSE detection limit. Our results highlight that the baryon cycle directly affects the dense neutral gas required for star-formation and plays a critical role in galaxy evolution.