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Cyberbullying victimization is prevalent and closely linked to mental health problems. However, existing research, often limited by cross-sectional designs and a focus on direct relationships, has yielded inconsistent results. Furthermore, the biological mechanisms underlying the relationship between cyberbullying victimization and psychopathological outcomes remain largely unclear at present. This retrospective cohort study aimed to explore the longitudinal associations among cyberbullying victimization, inhibitory control, brain activation during error processing, and mental health problems among adolescents. We curated the clinical, behavioral, and neuroimaging data (551/1186, 46.5% girls; 9-10 years at baseline) from the Adolescent Brain Cognitive Development study, a nationally representative cohort established through school-based probability sampling (selected factors included gender, race/ethnicity, socioeconomic status, and urbanicity). Participants were assessed by the cyberbullying question, the functional magnetic resonance imaging stop signal task for inhibitory control and error processing, and the Child Behavioral Checklist for externalizing and internalizing problems at 2-year (T1) and 4-year follow-up (T2). Linear mixed models were used to examine the retrospective longitudinal associations between these clinical, behavioral, and neuroimaging factors. Linear mixed models showed that victims of cyberbullying at T1 exhibited significantly greater externalizing problems at T2 (β=0.25, 95% CI 0.06-0.45, P =.02), but not for internalizing problems (β=-0.01, 95% CI -0.20 to 0.19, P =.99) or deficits in inhibitory control (Correct Stop Rate: β=-0.02, 95% CI -0.26 to 0.21, P =.85; Stop Signal Reaction Time: β=-0.07, 95% CI -0.27 to 0.13, P =.85). Furthermore, cyberbullying victimization at T1 contributed to higher activation in the bilateral superior parietal gyri (left: β=0.36, 95% CI 0.10-0.61, P =.04; right: β=0.34, 95% CI 0.08-0.59, P =.04), right inferior parietal gyrus (β=0.32, 95% CI 0.07-0.57, P =.04), and right posterior cingulate cortex (β=0.34, 95% CI 0.09-0.60, P =.04) during error processing at T2. However, these neural alterations did not significantly mediate between cyberbullying victimization at T1 and externalizing problems at T2. This longitudinal functional magnetic resonance imaging study investigates neural correlates of cyberbullying victimization in adolescents. By extending prior research that has relied primarily on cross-sectional or behavioral data, this research demonstrates that this form of victimization is associated with altered neural activation during error processing in later development. The pattern of nonsignificant impairment in inhibitory control and mediation to externalizing problems suggests that these neural impacts may be better characterized by a state of heightened sensitivity and compensatory engagement than by direct damage. Overall, this study points to the error-processing network as a potential target for cognitive interventions and establishes a foundation for further exploration of other neural mechanisms between cyberbullying victimization and mental health outcomes.

The JWST Disk Infrared Spectral Chemistry Survey (JDISCS) aims to understand the evolution of the chemistry of inner protoplanetary disks using the Mid-InfraRed Instrument (MIRI) on the James Webb Space Telescope (JWST). With a growing sample of >30 disks, the survey implements a custom method to calibrate the MIRI Medium Resolution Spectrometer (MRS) to contrasts of better than 1:300 across its 4.9–28 μm spectral range. This is achieved using observations of Themis family asteroids as precise empirical reference sources. The high spectral contrast enables precise retrievals of physical parameters, searches for rare molecular species and isotopologues, and constraints on the inventories of carbon- and nitrogen-bearing species. JDISCS also offers significant improvements to the MRS wavelength and resolving power calibration. We describe the JDISCS calibrated data and demonstrate their quality using observations of the disk around the solar-mass young star FZ Tau. The FZ Tau MIRI spectrum is dominated by strong emission from warm water vapor. We show that the water and CO line emission originates from the disk surface and traces a range of gas temperatures of ∼500–1500 K. We retrieve parameters for the observed CO and H2O lines and show that they are consistent with a radial distribution represented by two temperature components. A high water abundance of n(H2O) ∼ 10−4 fills the disk surface at least out to the 350 K isotherm at 1.5 au. We search the FZ Tau environs for extended emission, detecting a large (radius of ∼300 au) ring of emission from H2 gas surrounding FZ Tau, and discuss its origin.

Understanding when and how circumstellar disks disperse is crucial to constrain planet formation and migration. Thermal winds powered by high-energy stellar photons have long been theorized to drive disk dispersal. However, evidence for these winds is currently based only on small (∼3–6 km s−1) blueshifts in [Ne ii] 12.81 μm lines, which does not exclude MHD winds. We report JWST MIRI MRS spectro-imaging of T Cha, a disk with a large dust gap (∼30 au in radius) and blueshifted [Ne ii] emission. We detect four forbidden noble gas lines, [Ar ii], [Ar iii], [Ne ii], and [Ne iii], of which [Ar iii] is the first detection in any protoplanetary disk. We use line flux ratios to constrain the energy of the ionizing photons and find that argon is ionized by extreme ultraviolet, whereas neon is most likely ionized by X-rays. After performing continuum and point-spread function subtraction on the integral field unit cube, we discover a spatial extension in the [Ne ii] emission off the disk continuum emission. This is the first spatially resolved [Ne ii] disk wind emission. The mostly ionic spectrum of T Cha, in combination with the extended [Ne ii] emission, points to an evolved stage for any inner MHD wind and is consistent with the existence of an outer thermal wind ionized and driven by high-energy stellar photons. This work acts as a pathfinder for future observations aiming at investigating disk dispersal using JWST.

We present a MIRI-MRS spectrum of the high-inclination protoplanetary disk around the solar-mass (K0) star MY Lup, obtained as part of the JWST Disk Infrared Spectral Chemistry Survey (JDISCS). The spectrum shows an unusually weak water emission spectrum for a disk around a star of its spectral type, but strong emission from CO2, HCN, and isotopologues of both molecules. This includes the first ever detection of C18O16O and H13CN in an inner disk, as well as tentative detections of C17O16O and HC15N. Slab modeling provides the molecular temperatures, column densities, and emitting areas of the detected molecules. The emitting molecular gas is cold compared to that of other observed protoplanetary disk spectra. We estimate the isotopologue ratios of CO2 and HCN, albeit with significant uncertainty. We suggest that the unusual spectrum of MY Lup arises from a combination of inner-disk clearing, which removes emission from warm water, and its nearly edge-on inclination, which enhances line-of-sight column densities, although unusual chemistry may also be required. MY Lup’s spectrum highlights the potential to detect and measure trace isotopologues to study isotopic fractionation in protoplanetary disks; observations at higher spectral resolving power are needed to constrain the isotopologue ratios to greater precision.

This work aims at providing fundamental general tools for the analysis of water spectra as observed in protoplanetary disks with JWST-MIRI. We analyze 25 high-quality spectra from the JDISC Survey reduced with asteroid calibrators as presented in K. M. Pontoppidan et al. (2024). First, we present a spectral atlas to illustrate the clustering of H2O transitions from different upper-level energies (Eu) and identify single (unblended) transitions that provide the most reliable measurements. With that, we demonstrate two important excitation effects: the opacity saturation of ortho-para line pairs that overlap, and the subthermal excitation of excitation of v = 1–1 lines scattered across the v = 0–0 rotational band. Second, we define a shorter list of fundamental lines spanning Eu = 1500–6000 K to develop simple line-ratio diagnostic diagrams for the radial temperature distribution of water in inner disks, which are interpreted using discrete temperature components and power-law radial gradients. Third, we report the detection of disk-rotation Doppler broadening of molecular lines, which confirms the radial distribution of water emission including, for the first time, the radially extended ≈170–220 K reservoir close to the snowline. The combination of measured line ratios and broadening suggests that drift-dominated disks have shallower temperature gradients with an extended cooler disk surface enriched by ice sublimation. We also report the first detection of an H2O-rich inner disk wind from narrow blueshifted absorption in the ro-vibrational lines. We summarize these findings and tools into a general recipe to make the study of water in planet-forming regions reliable, effective, and sustainable for samples of >100 disks.

[Ne ii] 12.81 μm emission is a well-used tracer of protoplanetary disk winds due to its blueshifted line profile. Mid-Infrared Instrument (MIRI)-Medium Resolution Spectrometer (MRS) recently observed T Cha, detecting this line along with lines of [Ne iii], [Ar ii], and [Ar iii], with the [Ne ii] and [Ne iii] lines found to be extended while the [Ar ii] was not. In this complementary work, we use these lines to address long-debated questions about protoplanetary disk winds regarding their mass-loss rate, the origin of their ionization, and the role of magnetically driven winds as opposed to photoevaporation. To this end, we perform photoionization radiative transfer on simple hydrodynamic wind models to map the line emission. We compare the integrated model luminosities to those observed with MIRI-MRS to identify which models most closely reproduce the data and produce synthetic images from these to understand what information is captured by measurements of the line extents. Along with the low degree of ionization implied by the line ratios, the relative compactness of [Ar ii] compared to [Ne ii] is particularly constraining. This requires Ne ii production by hard X-rays and Ar ii production by soft X-rays (and/or EUV) in an extended (≳10 au) wind that is shielded from soft X-rays, necessitating a dense wind with material launched on scales down to ∼1 au. Such conditions could be produced by photoevaporation, whereas an extended magnetohydrodynamic (MHD) wind producing equal shielding would likely underpredict the line fluxes. However, a tenuous inner MHD wind may still contribute to shielding the extended wind. This picture is consistent with constraints from spectrally resolved line profiles.

Mid-infrared spectroscopy of protoplanetary disks provides a chemical inventory of gas within a few astronomical unit, where planets are readily detected around older stars. With the James Webb Space Telescope (JWST) Disk Infrared Spectral Chemistry Survey, we explore demographic trends among 31 disks observed with MIRI (MRS) and with previous Atacama Large Millimeter/submillimeter Array millimeter continuum imaging at high angular resolution (5–10 au). With these signal-to-noise ratio of ∼200–450 spectra, we report emission from H2O, OH, CO, C2H2, HCN, CO2, [Ne ii], [Ne iii], and [Ar ii]. Emission from H2O, OH, and CO is nearly ubiquitous for low-mass stars, and detection rates of all molecules are higher than for similar disks observed with Spitzer-IRS. Slab model fits to the molecular emission lines demonstrate that emission from C2H2, HCN, and possibly CO2 is optically thin; thus since column densities and emitting radii are degenerate, observations are actually sensitive to the total molecular mass. C2H2 and HCN emission also typically originate in a hotter region ( 920−130+70 , 820−130+70 K, respectively) than CO2 ( 600−160+200 K). The HCN to cold H2O luminosity ratios are generally smaller in smooth disks, consistent with more efficient water delivery via icy pebbles in the absence of large dust substructures. The molecular emission-line luminosities are also correlated with mass accretion rates and infrared spectral indices, similar to trends reported from Spitzer-IRS surveys. This work demonstrates the power of combining multiwavelength observations to explore inner disk chemistry as a function of outer disk and stellar properties, which will continue to grow as the sample of observed Class II systems expands in the coming JWST observation cycles.

We present a JWST MIRI/MRS spectrum of the inner disk of WISE J044634.16–262756.1B (hereafter J0446B), an old (∼34 Myr) M4.5 star but with hints of ongoing accretion. The spectrum is molecule-rich and dominated by hydrocarbons. We detect 14 molecular species (H2, CH3, CH4, C2H2, 13CCH2, C2H4, C2H6, C3H4, C4H2, C6H6, HCN, HC3N, CO2, and 13CO2) and two atomic lines ([Ne ii] and [Ar ii]), all observed for the first time in a disk at this age. The detection of spatially unresolved H2 and Ne gas strongly supports that J0446B hosts a long-lived primordial disk, rather than a debris disk. The marginal H2O detection and the high C2H2/CO2 column density ratio indicate that the inner disk of J0446B has a very carbon-rich chemistry, with a gas-phase C/O ratio ≳2, consistent with what has been found in most primordial disks around similarly low-mass stars. In the absence of significant outer disk dust substructures, inner disks are expected to first become water-rich due to the rapid inward drift of icy pebbles and evolve into carbon-rich as outer disk gas flows inward on longer timescales. The faint millimeter emission in such low-mass star disks implies that they may have depleted their outer icy pebble reservoir early and already passed the water-rich phase. Models with pebble drift and volatile transport suggest that maintaining a carbon-rich chemistry for tens of Myr likely requires a slowly evolving disk with α-viscosity ≲10−4. This study represents the first detailed characterization of disk gas at ∼30 Myr, strongly motivating further studies into the final stages of disk evolution.

We present an analysis of the JDISCS JWST/MIRI-MRS spectrum of Sz 114, an accreting M5 star surrounded by a large dust disk with a shallow gap at ∼39 au. The spectrum is molecule-rich; we report the detection of water, CO, CO2, HCN, C2H2, and H2. The only identified atomic/ionic transition is from [Ne ii] at 12.81 μm. A distinct feature of this spectrum is the forest of water lines with the 17.22 μm emission surpassing that of most mid-to-late M star disks by an order of magnitude in flux and aligning instead with disks of earlier-type stars. Moreover, the flux ratios of C2H2/H2O and HCN/H2O in Sz 114 also resemble those of earlier-type disks, with a slightly elevated CO2/H2O ratio. While accretional heating can boost all infrared lines, the unusual properties of Sz 114 could be explained by the young age of the source, its formation under unusual initial conditions (a large massive disk), and the presence of dust substructures. The latter delays the inward drift of icy pebbles and helps preserve a lower C/O ratio over an extended period. In contrast, mid-to-late M-star disks—which are typically faint, small in size, and likely lack significant substructures—may have more quickly depleted the outer icy reservoir and already evolved out of a water-rich inner disk phase. Our findings underscore the unexpected diversity within mid-infrared spectra of mid-to-late M-star disks, highlighting the need to expand the observational sample for a comprehensive understanding of their variations and thoroughly test pebble drift and planet formation models.

We analyze JWST/MIRI observations of T Cha, a highly variable (ΔV ∼ 3–5 mag) accreting Sun-like star surrounded by a disk with a large (∼15 au) dust gap. We find that the JWST mid-IR spectrum is significantly different from the Spitzer spectrum obtained 17 yr before—the emission at short wavelengths (5–10 μm) has decreased by ∼2/3 while that at longer wavelengths (15–25 μm) has increased by up to a factor of ∼3. The JWST spectrum is contemporaneous with a fairly constant higher optical emission captured by the All Sky Automated Survey. After analyzing and modeling both spectral energy distributions, we propose that JWST caught the star during an outburst that partly destroyed and significantly reduced the height of the asymmetric inner disk wall responsible for the high optical variability and lower 15–25 μm emission during the Spitzer period. The dust mass lost during this outburst is estimated to be comparable (∼1/5) to the upper limit of the total micron-sized dust mass in the inner disk of T Cha now. Monitoring this system during possible future outbursts and more observations of its quiescent state will reveal if the inner disk can be replenished or will continue to be depleted and vanish.