Journal Supplement Research Articles

Preface.

The field of diuretic therapy has witnessed significant advancements over the decades. Loop diuretics and other diuretic agents are crucial in the management of various conditions characterized by fluid overload. Torsemide, a loop diuretic agent, has unique pharmacological properties, safety profiles, and varied clinical applications. This special journal supplement aims to provide a comprehensive examination of torsemide, highlighting its role in contemporary medical practice.

Advancing Diagnosis of Current Hepatitis C Virus Infection: A Key to Hepatitis C Elimination in the United States.

More than 2 million adults have hepatitis C virus (HCV) infection in the United States, and new infections continue to increase. Without treatment, HCV infection can lead to advanced liver disease and death. Treatment is recommended for nearly everyone with hepatitis C, resulting in a cure in >95% of people treated and raising the possibility of hepatitis C elimination. Testing is the first step to accessing life-saving treatment. The Centers for Disease Control and Prevention recommends hepatitis C screening for all adults, all pregnant persons, and anyone with risk; yet about one-third of people with hepatitis C remain unaware of their infection. Testing begins with a hepatitis C antibody test, followed, when reactive, by a nucleic acid test to detect HCV RNA. This antibody-first, 2-step testing strategy misses early infections and can result in incomplete diagnoses. Advancements in hepatitis C diagnostics and the US regulatory landscape have created an opportunity to include viral-first testing strategies and improve hepatitis C diagnosis. This journal supplement features 8 articles detailing challenges and opportunities for improving hepatitis C diagnostics in support of advancing hepatitis C elimination in the United States.

Foreword: Preventing COVID-19 Among the Immunocompromised Population.

The COVID-19 pandemic represented 1 of the more significant and unique public health challenges facing the global community, particularly afflicting those with compromised immune systems. These immunocompromised individuals were readily recognized as a group at high risk of infection by SARS-CoV-2 and the associated severe outcomes of COVID-19. Although preventive strategies such as vaccination are important, initial clinical vaccine trials did not enroll immunocompromised individuals; in-depth evaluations of the safety, immunogenicity, and real-world outcomes associated with these vaccines were conducted in this population thereafter. As immunogenicity data of COVID-19 vaccination among this disparate group of individuals emerged, vaccination strategies were adapted to address outstanding challenges and further protect the entirety of this population. This 8-part journal supplement characterizes in-depth the mRNA-based COVID-19 vaccination strategies across the spectrum of immunocompromised individuals, focusing on the ongoing approaches to challenges facing this group as the pandemic continues to evolve.

Why we need to re‐define long‐term success for people living with HIV

Over the past few decades, the life expectancy of people living with HIV has markedly improved due to the advances in HIV diagnosis, linkage to care, and treatment. However, with these advances, a new set of challenges has emerged that must be addressed to ensure the long-term well-being of people living with HIV. In this article, as part of a wider journal supplement, we explore the unmet needs and challenges across the HIV continuum of care and re-define what long-term success looks like to support the healthy ageing of all people affected by HIV.

Authors: Improve Your Bibliometrics with Digital Enhancements

It has been hypothesized that articles that practice open science have out-sized impact in their communities. We have analyzed four years of citation data of the Astrophysical Journal, the Astrophysical Journal Letters, the Astrophysical Journal Supplement, and the Astronomical Journal to investigate if including data and enhanced figure displays increases citations. Articles with these enhanced digital assets have equal or higher citations than articles without these products. The implication is that authors that take the time to include or link to underlying tabular and figure data or utilize enhanced graphics, i.e., animations or interactive figures, reap bibliometric benefits.

Abstracts From the 2022 Health Care Systems Research Network (HCSRN) Annual Conference.

The Health Care Systems Research Network (HCSRN) is comprised of 20 health systems with embedded research units. The network’s annual conference serves as a forum for research teams from member institutions to disseminate scientific findings, explore new collaborations, and share insights about conducting research in real-world care delivery settings. Abstracts accepted for presentation at HCSRN 2022 are published in this supplement of Journal of Patient-Centered Research and Reviews, the official journal of HCSRN’s annual conference proceedings.

Rationale and Approach to Evaluating Interventions to Promote Child Health in LMICs.

Rationale and Approach to Evaluating Interventions to Promote Child Health in LMICs.

Fitting a vaccine into the HIV prevention landscape.

Fitting a vaccine into the HIV prevention landscape.

Molecules with ALMA at Planet-forming Scales (MAPS). XI. CN and HCN as Tracers of Photochemistry in Disks

Abstract UV photochemistry in the surface layers of protoplanetary disks dramatically alters their composition relative to previous stages of star formation. The abundance ratio CN/HCN has long been proposed to trace the UV field in various astrophysical objects; however, to date the relationship between CN, HCN, and the UV field in disks remains ambiguous. As part of the ALMA Large Program MAPS (Molecules with ALMA at Planet-forming Scales), we present observations of CN N = 1–0 transitions at 0.″3 resolution toward five disk systems. All disks show bright CN emission within ∼50–150 au, along with a diffuse emission shelf extending up to 600 au. In all sources we find that the CN/HCN column density ratio increases with disk radius from about unity to 100, likely tracing increased UV penetration that enhances selective HCN photodissociation in the outer disk. Additionally, multiple millimeter dust gaps and rings coincide with peaks and troughs, respectively, in the CN/HCN ratio, implying that some millimeter substructures are accompanied by changes to the UV penetration in more elevated disk layers. That the CN/HCN ratio is generally high (>1) points to a robust photochemistry shaping disk chemical compositions and also means that CN is the dominant carrier of the prebiotically interesting nitrile group at most disk radii. We also find that the local column densities of CN and HCN are positively correlated despite emitting from vertically stratified disk regions, indicating that different disk layers are chemically linked. This paper is part of the MAPS special issue of the Astrophysical Journal Supplement.

Molecules with ALMA at Planet-forming Scales (MAPS). VII. Substellar O/H and C/H and Superstellar C/O in Planet-feeding Gas

Abstract The elemental composition of the gas and dust in a protoplanetary disk influences the compositions of the planets that form in it. We use the Molecules with ALMA at Planet-forming Scales (MAPS) data to constrain the elemental composition of the gas at the locations of potentially forming planets. The elemental abundances are inferred by comparing source-specific gas-grain thermochemical models with variable C/O ratios and small-grain abundances from the DALI code with CO and C2H column densities derived from the high-resolution observations of the disks of AS 209, HD 163296, and MWC 480. Elevated C/O ratios (∼2.0), even within the CO ice line, are necessary to match the inferred C2H column densities over most of the pebble disk. Combined with constraints on the CO abundances in these systems, this implies that both the O/H and C/H ratios in the gas are substellar by a factor of 4–10, with the O/H depleted by a factor of 20–50, resulting in the high C/O ratios. This necessitates that even within the CO ice line, most of the volatile carbon and oxygen is still trapped on grains in the midplane. Planets accreting gas in the gaps of the AS 209, HD 163296, and MWC 480 disks will thus acquire very little carbon and oxygen after reaching the pebble isolation mass. In the absence of atmosphere-enriching events, these planets would thus have a strongly substellar O/H and C/H and superstellar C/O atmospheric composition. This paper is part of the MAPS special issue of the Astrophysical Journal Supplement.

Molecules with ALMA at Planet-forming Scales (MAPS). IV. Emission Surfaces and Vertical Distribution of Molecules

Abstract The Molecules with ALMA at Planet-forming Scales (MAPS) Large Program provides a unique opportunity to study the vertical distribution of gas, chemistry, and temperature in the protoplanetary disks around IM Lup, GM Aur, AS 209, HD 163296, and MWC 480. By using the asymmetry of molecular line emission relative to the disk major axis, we infer the emission height (z) above the midplane as a function of radius (r). Using this method, we measure emitting surfaces for a suite of CO isotopologues, HCN, and C2H. We find that 12CO emission traces the most elevated regions with z / r > 0.3 , while emission from the less abundant 13CO and C18O probes deeper into the disk at altitudes of z / r ≲ 0.2 . C2H and HCN have lower opacities and signal-to-noise ratios, making surface fitting more difficult, and could only be reliably constrained in AS 209, HD 163296, and MWC 480, with z / r ≲ 0.1 , i.e., relatively close to the planet-forming midplanes. We determine peak brightness temperatures of the optically thick CO isotopologues and use these to trace 2D disk temperature structures. Several CO temperature profiles and emission surfaces show dips in temperature or vertical height, some of which are associated with gaps and rings in line and/or continuum emission. These substructures may be due to local changes in CO column density, gas surface density, or gas temperatures, and detailed thermochemical models are necessary to better constrain their origins and relate the chemical compositions of elevated disk layers with those of planet-forming material in disk midplanes. This paper is part of the MAPS special issue of the Astrophysical Journal Supplement.

Molecules with ALMA at Planet-forming Scales (MAPS). XVIII. Kinematic Substructures in the Disks of HD 163296 and MWC 480

Abstract We explore the dynamical structure of the protoplanetary disks surrounding HD 163296 and MWC 480 as part of the Molecules with ALMA at Planet-forming Scales (MAPS) large program. Using the J = 2–1 transitions of 12CO, 13CO, and C18O imaged at spatial resolutions of ∼0.″15 and with a channel spacing of 200 m s−1, we find perturbations from Keplerian rotation in the projected velocity fields of both disks (≲5% of the local Keplerian velocity), suggestive of large-scale (tens of astronomical units in size), coherent flows. By accounting for the azimuthal dependence on the projection of the velocity field, the velocity fields were decomposed into azimuthally averaged orthogonal components, v ϕ , v r , and v z . Using the optically thick 12CO emission as a probe of the gas temperature, local variations of ≈3 K (≈5% relative changes) were observed and found to be associated with the kinematic substructures. The MWC 480 disk hosts a suite of tightly wound spiral arms. The spirals arms, in conjunction with the highly localized perturbations in the gas velocity structure (kinematic planetary signatures), indicate a giant planet, ∼1 M Jup, at a radius of ≈245 au. In the disk of HD 163296, the kinematic substructures were consistent with previous studies of Pinte et al. and Teague et al. advocating for multiple ∼1 M Jup planets embedded in the disk. These results demonstrate that molecular line observations that characterize the dynamical structure of disks can be used to search for the signatures of embedded planets. This paper is part of the MAPS special issue of the Astrophysical Journal Supplement.

Molecules with ALMA at Planet-forming Scales (MAPS). XIX. Spiral Arms, a Tail, and Diffuse Structures Traced by CO around the GM Aur Disk

Abstract The concentric gaps and rings commonly observed in protoplanetary disks in millimeter continuum emission have lent the impression that planet formation generally proceeds within orderly, isolated systems. While deep observations of spatially resolved molecular emission have been comparatively limited, they are increasingly suggesting that some disks interact with their surroundings while planet formation is underway. We present an analysis of complex features identified around GM Aur in 12CO J = 2 − 1 images at a spatial resolution of ∼40 au. In addition to a Keplerian disk extending to a radius of ∼550 au, the CO emission traces flocculent spiral arms out to radii of ∼1200 au, a tail extending ∼1800 au southwest of GM Aur, and diffuse structures extending from the north side of the disk up to radii of ∼1900 au. The diffuse structures coincide with a “dust ribbon” previously identified in scattered light. The large-scale asymmetric gas features present a striking contrast with the mostly axisymmetric, multi-ringed millimeter continuum tracing the pebble disk. We hypothesize that GM Aur’s complex gas structures result from late infall of remnant envelope or cloud material onto the disk. The morphological similarities to the SU Aur and AB Aur systems, which are also located in the L1517 cloud, provide additional support to a scenario in which interactions with the environment are playing a role in regulating the distribution and transport of material in all three of these Class II disk systems. This paper is part of the MAPS special issue of the Astrophysical Journal Supplement.

Molecules with ALMA at Planet-forming Scales (MAPS). XVI. Characterizing the Impact of the Molecular Wind on the Evolution of the HD 163296 System

Abstract During the main phase of evolution of a protoplanetary disk, accretion regulates the inner-disk properties, such as the temperature and mass distribution, and in turn, the physical conditions associated with planet formation. The driving mechanism behind accretion remains uncertain; however, one promising mechanism is the removal of a fraction of angular momentum via a magnetohydrodynamic (MHD) disk wind launched from the inner tens of astronomical units of the disk. This paper utilizes CO isotopologue emission to study the unique molecular outflow originating from the HD 163296 protoplanetary disk obtained with the Atacama Large Millimeter/submillimeter Array. HD 163296 is one of the most well-studied Class II disks and is proposed to host multiple gas-giant planets. We robustly detect the large-scale rotating outflow in the 12CO J = 2 − 1 and the 13CO J = 2 − 1 and J = 1 − 0 transitions. We constrain the kinematics, the excitation temperature of the molecular gas, and the mass-loss rate. The high ratio of the rates of ejection to accretion (5–50), together with the rotation signatures of the flow, provides solid evidence for an MHD disk wind. We find that the angular momentum removal by the wind is sufficient to drive accretion though the inner region of the disk; therefore, accretion driven by turbulent viscosity is not required to explain HD 163296's accretion. The low temperature of the molecular wind and its overall kinematics suggest that the MHD disk wind could be perturbed and shocked by the previously observed high-velocity atomic jet. This paper is part of the MAPS special issue of the Astrophysical Journal Supplement.

Molecules with ALMA at Planet-forming Scales (MAPS). XIV. Revealing Disk Substructures in Multiwavelength Continuum Emission

Abstract Constraining dust properties of planet-forming disks via high-angular-resolution observations is fundamental to understanding how solids are trapped in substructures and how dust growth may be favored or accelerated therein. We use ALMA dust continuum observations of the Molecules with ALMA at Planet-forming Scales (MAPS) disks and explore a large parameter space to constrain the radial distribution of solid mass and maximum grain size in each disk, including or excluding dust scattering. In the nonscattering model, the dust surface density and maximum grain size profiles decrease from the inner disks to the outer disks, with local maxima at the bright ring locations, as expected from dust trapping models. The inferred maximum grain sizes from the inner to outer disks decrease from 1 cm to 1 mm. For IM Lup, HD 163296, and MWC 480 in the scattering model, two solutions are compatible with their observed inner disk emission: one solution corresponding to a maximum grain size of a few millimeters (similar to the nonscattering model), and the other corresponding to a size of a few hundred micrometers. Based on the estimated Toomre parameter, only IM Lup—which shows a prominent spiral morphology in millimeter dust—is found to be gravitationally unstable. The estimated maximum Stokes number in all the disks lies between 0.01 and 0.3, and the estimated turbulence parameters in the rings of AS 209 and HD 163296 are close to the threshold where dust growth is limited by turbulent fragmentation. This paper is part of the MAPS special issue of the Astrophysical Journal Supplement.

Molecules with ALMA at Planet-forming Scales (MAPS). IX. Distribution and Properties of the Large Organic Molecules HC3N, CH3CN, and c-C3H2

Abstract The precursors to larger, biologically relevant molecules are detected throughout interstellar space, but determining the presence and properties of these molecules during planet formation requires observations of protoplanetary disks at high angular resolution and sensitivity. Here, we present 0.″3 observations of HC3N, CH3CN, and c-C3H2 in five protoplanetary disks observed as part of the Molecules with ALMA at Planet-forming Scales (MAPS) Large Program. We robustly detect all molecules in four of the disks (GM Aur, AS 209, HD 163296, and MWC 480) with tentative detections of c-C3H2 and CH3CN in IM Lup. We observe a range of morphologies—central peaks, single or double rings—with no clear correlation in morphology between molecule or disk. Emission is generally compact and on scales comparable with the millimeter dust continuum. We perform both disk-integrated and radially resolved rotational diagram analysis to derive column densities and rotational temperatures. The latter reveals 5–10 times more column density in the inner 50–100 au of the disks when compared with the disk-integrated analysis. We demonstrate that CH3CN originates from lower relative heights in the disks when compared with HC3N, in some cases directly tracing the disk midplane. Finally, we find good agreement between the ratio of small to large nitriles in the outer disks and comets. Our results indicate that the protoplanetary disks studied here are host to significant reservoirs of large organic molecules, and that this planet- and comet-building material can be chemically similar to that in our own solar system. This paper is part of the MAPS special issue of the Astrophysical Journal Supplement.

Molecules with ALMA at Planet-forming Scales (MAPS). XIII. HCO+ and Disk Ionization Structure

Abstract We observed HCO+ J = 1 − 0 and H13CO+ J = 1 − 0 emission toward the five protoplanetary disks around IM Lup, GM Aur, AS 209, HD 163296, and MWC 480 as part of the MAPS project. HCO+ is detected and mapped at 0.″3 resolution in all five disks, while H13CO+ is detected (S/N > 6σ) toward GM Aur and HD 163296 and tentatively detected (S/N > 3σ) toward the other disks by a matched filter analysis. Inside a radius of R ∼ 100 au, the HCO+ column density is flat or shows a central dip. At outer radii (≳100 au), the HCO+ column density decreases outward, while the column density ratio of HCO+/CO is mostly in the range of ∼10−5–10−4. We derived the HCO+ abundance in the warm CO-rich layer, where HCO+ is expected to be the dominant molecular ion. At R ≳ 100 au, the HCO+ abundance is ∼3 × 10−11 − 3 × 10−10, which is consistent with a template disk model with X-ray ionization. At the smaller radii, the abundance decreases inward, which indicates that the ionization degree is lower in denser gas, especially inside the CO snow line, where the CO-rich layer is in the midplane. Comparison of template disk models with the column densities of HCO+, N2H+, and N2D+ indicates that the midplane ionization rate is ≳10−18 s−1 for the disks around IM Lup, AS 209, and HD 163296. We also find hints of an increased HCO+ abundance around the location of dust continuum gaps in AS 209, HD 163296, and MWC 480. This paper is part of the MAPS special issue of the Astrophysical Journal Supplement.

Molecules with ALMA at Planet-forming Scales (MAPS). VI. Distribution of the Small Organics HCN, C2H, and H2CO

Abstract Small organic molecules, such as C2H, HCN, and H2CO, are tracers of the C, N, and O budget in protoplanetary disks. We present high-angular-resolution (10–50 au) observations of C2H, HCN, and H2CO lines in five protoplanetary disks from the Molecules with ALMA at Planet-forming Scales (MAPS) ALMA Large Program. We derive column density and excitation temperature profiles for HCN and C2H, and find that the HCN emission arises in a temperate (20–30 K) layer in the disk, while C2H is present in relatively warmer (20–60 K) layers. In the case of HD 163296, we find a decrease in column density for HCN and C2H inside one of the dust gaps near ∼83 au, where a planet has been proposed to be located. We derive H2CO column density profiles assuming temperatures between 20 and 50 K, and find slightly higher column densities in the colder disks around T Tauri stars than around Herbig Ae stars. The H2CO column densities rise near the location of the CO snowline and/or millimeter dust edge, suggesting an efficient release of H2CO ices in the outer disk. Finally, we find that the inner 50 au of these disks are rich in organic species, with abundances relative to water that are similar to cometary values. Comets could therefore deliver water and key organics to future planets in these disks, similar to what might have happened here on Earth. This paper is part of the MAPS special issue of the Astrophysical Journal Supplement.

Molecules with ALMA at Planet-forming Scales (MAPS). XV. Tracing Protoplanetary Disk Structure within 20 au

Abstract Constraining the distribution of gas and dust in the inner 20 au of protoplanetary disks is difficult. At the same time, this region is thought to be responsible for most planet formation, especially around the water ice line at 3–10 au. Under the assumption that the gas is in a Keplerian disk, we use the exquisite sensitivity of the Molecules with ALMA at Planet-forming Scales (MAPS) ALMA large program to construct radial surface brightness profiles with a ∼3 au effective resolution for the CO isotopologue J = 2–1 lines using the line velocity profile. IM Lup reveals a central depression in 13CO and C18O that is ascribed to a pileup of ∼500 M ⊕ of dust in the inner 20 au, leading to a gas-to-dust ratio of around <10. This pileup is consistent with an efficient drift of grains (≳100 M ⊕ Myr−1) and a local gas-to-dust ratio that suggests that the streaming instability could be active. The CO isotopologue emission in the GM Aur disk is consistent with a small (∼15 au), strongly depleted gas cavity within the ∼40 au dust cavity. The radial surface brightness profiles for both the AS 209 and HD 163296 disks show a local minimum and maximum in the C18O emission at the location of a known dust ring (∼14 au) and gap (∼10 au), respectively. This indicates that the dust ring has a low gas-to-dust ratio (>10) and that the dust gap is gas-rich enough to have optically thick C18O. This paper is part of the MAPS special issue of the Astrophysical Journal Supplement.

Molecules with ALMA at Planet-forming Scales (MAPS). XVII. Determining the 2D Thermal Structure of the HD 163296 Disk

Abstract Understanding the temperature structure of protoplanetary disks is key to interpreting observations, predicting the physical and chemical evolution of the disk, and modeling planet formation processes. In this study, we constrain the two-dimensional thermal structure of the disk around the Herbig Ae star HD 163296. Using the thermochemical code RAC2D, we derive a thermal structure that reproduces spatially resolved Atacama Large Millimeter/submillimeter Array observations (∼0.″12 (13 au)–0.″25 (26 au)) of 12CO J = 2 − 1, 13CO J = 1 − 0, 2 − 1, C18O J = 1 − 0, 2 − 1, and C17O J = 1 − 0, the HD J = 1 − 0 flux upper limit, the spectral energy distribution (SED), and continuum morphology. The final model incorporates both a radial depletion of CO motivated by a timescale shorter than typical CO gas-phase chemistry (0.01 Myr) and an enhanced temperature near the surface layer of the the inner disk (z/r ≥ 0.21). This model agrees with the majority of the empirically derived temperatures and observed emitting surfaces derived from the J = 2 − 1 CO observations. We find an upper limit for the disk mass of 0.35 M ⊙, using the upper limit of the HD J = 1 − 0 and J = 2 − 1 flux. With our final thermal structure, we explore the impact that gaps have on the temperature structure constrained by observations of the resolved gaps. Adding a large gap in the gas and small dust additionally increases gas temperature in the gap by only 5%–10%. This paper is part of the MAPS special issue of the Astrophysical Journal Supplement.