Importance:As generative artificial intelligence (GenAI) tools become increasingly integrated into the daily lives of youth, it is critical to study their usage patterns and potential implications for mental health. While there is evidence of a rapid pace of adoption among adults, rates of GenAI use among youth remains largely undocumented. Objective:To characterize GenAI application (app) usage among US youth, including adoption rates and time spent. Design, Setting, and Participants:This cross-sectional study documented digital behavior of US youth extracted from a parental monitoring app. Participants were ages 4 to 17 years and were in families using a commercially available Aura app in the US. No identifying information was collected about the child except year of birth. Data were collected using passive sensing methods from naturalistic smart device use between September 2024 and April 2025. Data were analyzed in May and June 2025. Main Outcome and Measures:Adoption rates (ie, number of youth ever accessing GenAI apps on their device) and time spent using GenAI (ie, average minutes accessing GenAI apps), measured by age and time period. Results:In a cohort of 6488 participants, nearly 2072 youths (31.9%) used GenAI apps on their device. GenAI use was highest among teens (age 13 to 14 years, 899 of 2139 [42.0%]; age 15 to 17 years, 628 of 1246 [50.4%]), although adoption among preteens (age 10 to 12 years, 484 of 2366 [20.5%]) and school-aged children (age 8 to 9 years, 49 of 522 [9.4%]) was not trivial. GenAI usage was higher after school than at nighttime or during school. Overall, users spent a mean (SD) 2.37 (10.55) and a median (IQR) 0.18 (0.04-0.84) minutes a day using GenAI, yet large variances and skewed distributions suggest that a small subset of youth use GenAI extensively, with the heaviest users accessing GenAI for over 40 minutes a day. Conclusions and Relevance:In this cross-sectional study, Gen AI app use varied widely among participants, with up to half of adolescents having some use and a small subset engaging in heavy use. Future research must address individual differences in GenAI use to determine impacts on development.
We present 21 transients from our three-epoch, four-band NIRCam observations covering 14.16 arcmin ^2 in the Spitzer IRAC Dark Field (IDF), taken by the JWST Prime Extragalactic Areas for Reionization and Lensing Science program with a time cadence of ∼6 months. A separate Hubble Space Telescope program provided Advanced Camera for Surveys optical imaging contemporaneous with the second and third epochs of the NIRCam observations. The NIRSpec spectroscopy on three transients confirmed a Type Ia supernova at z = 1.63 and the host galaxies of the other two at z = 2.64 and 1.90, respectively. Combining these with the photometric redshifts ( z _ph ) of the host galaxies in the rest of the sample, we find that the transients are in either a “mid- z ” group at z > 1.6 with M _V ≲ − 16.0 mag or a “low- z ” group at z < 0.4 with M _H ≳ − 14.0 mag. The mid- z transients are consistent with supernovae. In contrast, the low- z transients’ luminosities fall in the range of the so-called “gap transients” between supernovae and novae. However, this latter conclusion is only tentative due to possible catastrophic failures in z _ph that could bias them to low- z . Conversely, if they are indeed at z < 0.4, it would be worth studying similar transients in the future. Our work further demonstrates the power of NIRCam in transient science and also shows that it would be more fruitful to carry out a long-term monitoring program with more passbands, a higher cadence, and prompt follow-up spectroscopy. Being in the continuous viewing zone of the JWST, the IDF is an ideal field for this purpose.
Superficial fungal infections, mainly caused by dermatophytes but also by yeasts or molds, exhibit wide clinical variability and are a common reason for medical consultation. Recent epidemiological trends, particularly the emergence of extensive cutaneous dermatophytoses, -highlight the need for rigorous mycological diagnosis. The development of nucleic acid amplification techniques (NAAT) and advances in proteomics (MALDI-TOF) have prompted a reassessment of the role of conventional methods, without replacing them. These recommendations aim to guide biologists and COFRAC auditors in selecting and implementing the various available techniques, in order to harmonize practices and improve the overall quality of mycological diagnosis.
We present updated encircled energy (EE) curves for a subset of UVIS filters. These are derived from a reanalysis of the drizzled Point Spread Function (PSF) data underlying the current EE calibration together with new measurements from deep observations of the PSF wings. Improved centroiding and analysis techniques applied to the drizzled PSFs produce more accurate EE values at small radii (r ≤ 10 pixels), bringing the results into closer agreement with a large archival PSF study (Huynh et al. 2025). At large radii, we leverage deep observations of the PSF wings in six filters and compare the fraction of light between 2" and 6" with predictions from an optical model of the PSF (Hartig 2009). For filters with pivot wavelengths ≳4000A, the model agrees with the empirical data, but over-estimates the EE for UV filters by ∼0.5
We report a survey of molecular emission from cometary volatiles using the James Webb Space Telescope (JWST) toward Oort cloud comet C/2022 E3 (ZTF) carried out on UT 2023 February 28 and March 1 at a heliocentric distance (rH) of 1.33 au. These measurements of H2O, HCN, CH3OH, C2H6, CH4, CO, CO2, 13CO2, and OCS sampled post-perihelion molecular chemistry in C/2022 E3. A suite of near to mid-infrared OH (prompt emission) transitions were also detected. This work presents nucleus-centered spectra for all detected species, spatial-spectral maps of column density and rotational temperature as a function of distance from the nucleus for all except C2H6, HCN, and OH, and maps of co-measured continuum. The spatial distributions of both quantities were anisotropic for all mapped molecules; however, H2O showed distributions distinct from the remaining species. Coma-averaged values of the ortho-to-para ratio (OPR) for H2O and the 12CO2/13CO2 ratio derived from these maps were consistent with the statistical equilibrium value of 3 and the terrestrial value of 89, respectively. The modeled mass fraction of the sub-micron dust grains is dominated by amorphous carbon (56
